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+# Calculation Engine - Formula Function Reference
+
+## Frequently asked questions
+
+The up-to-date F.A.Q. page for PHPExcel can be found on [http://www.codeplex.com/PHPExcel/Wiki/View.aspx?title=FAQ&referringTitle=Requirements][1].
+
+### Formulas don’t seem to be calculated in Excel2003 using compatibility pack?
+
+This is normal behaviour of the compatibility pack, Excel2007 displays this correctly. Use PHPExcel_Writer_Excel5 if you really need calculated values, or force recalculation in Excel2003.
+
+  [1]: http://www.codeplex.com/PHPExcel/Wiki/View.aspx?title=FAQ&referringTitle=Requirements
diff --git a/Documentation/markdown/CalculationEngine/FunctionReference/02-01-Date-and-Time-Handling.md b/Documentation/markdown/CalculationEngine/FunctionReference/02-01-Date-and-Time-Handling.md
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+# Calculation Engine - Formula Function Reference
+
+## Function Reference
+
+### Handling Date and Time Values
+
+#### Excel functions that return a Date and Time value
+
+Any of the Date and Time functions that return a date value in Excel can return either an Excel timestamp or a PHP timestamp or date object.
+
+It is possible for scripts to change the data type used for returning date values by calling the PHPExcel_Calculation_Functions::setReturnDateType() method:
+
+```php
+PHPExcel_Calculation_Functions::setReturnDateType($returnDateType);
+```
+
+where the following constants can be used for $returnDateType
+
+ - PHPExcel_Calculation_Functions::RETURNDATE_PHP_NUMERIC
+ - PHPExcel_Calculation_Functions::RETURNDATE_PHP_OBJECT
+ - PHPExcel_Calculation_Functions::RETURNDATE_EXCEL
+
+The method will return a Boolean True on success, False on failure (e.g. if an invalid value is passed in for the return date type).
+
+The PHPExcel_Calculation_Functions::getReturnDateType() method can be used to determine the current value of this setting:
+
+```php
+$returnDateType = PHPExcel_Calculation_Functions::getReturnDateType();
+```
+
+The default is RETURNDATE_PHP_NUMERIC.
+
+##### PHP Timestamps
+
+If RETURNDATE_PHP_NUMERIC is set for the Return Date Type, then any date value returned to the calling script by any access to the Date and Time functions in Excel will be an integer value that represents the number of seconds from the PHP/Unix base date. The PHP/Unix base date (0) is 00:00 UST on 1st January 1970. This value can be positive or negative: so a value of -3600 would be 23:00 hrs on 31st December 1969; while a value of +3600 would be 01:00 hrs on 1st January 1970. This gives PHP a date range of between 14th December 1901 and 19th January 2038.
+
+##### PHP DateTime Objects
+
+If the Return Date Type is set for RETURNDATE_PHP_NUMERIC, then any date value returned to the calling script by any access to the Date and Time functions in Excel will be a PHP date/time object.
+
+##### Excel Timestamps
+
+If RETURNDATE_EXCEL is set for the Return Date Type, then the returned date value by any access to the Date and Time functions in Excel will be a floating point value that represents a number of days from the Excel base date. The Excel base date is determined by which calendar Excel uses: the Windows 1900 or the Mac 1904 calendar. 1st January 1900 is the base date for the Windows 1900 calendar while 1st January 1904 is the base date for the Mac 1904 calendar.
+
+It is possible for scripts to change the calendar used for calculating Excel date values by calling the PHPExcel_Shared_Date::setExcelCalendar() method:
+
+```php
+PHPExcel_Shared_Date::setExcelCalendar($baseDate);
+```
+
+where the following constants can be used for $baseDate
+
+ - PHPExcel_Shared_Date::CALENDAR_WINDOWS_1900
+ - PHPExcel_Shared_Date::CALENDAR_MAC_1904
+
+The method will return a Boolean True on success, False on failure (e.g. if an invalid value is passed in).
+
+The PHPExcel_Shared_Date::getExcelCalendar() method can be used to determine the current value of this setting:
+
+```php
+$baseDate = PHPExcel_Shared_Date::getExcelCalendar();
+```
+The default is CALENDAR_WINDOWS_1900.
+
+##### Functions that return a Date/Time Value
+
+ - DATE
+ - DATEVALUE
+ - EDATE
+ - EOMONTH
+ - NOW
+ - TIME
+ - TIMEVALUE
+ - TODAY
+
+#### Excel functions that accept Date and Time values as parameters
+
+Date values passed in as parameters to a function can be an Excel timestamp or a PHP timestamp; or date object; or a string containing a date value (e.g. '1-Jan-2009'). PHPExcel will attempt to identify their type based on the PHP datatype:
+
+An integer numeric value will be treated as a PHP/Unix timestamp. A real (floating point) numeric value will be treated as an Excel date/timestamp. Any PHP DateTime object will be treated as a DateTime object. Any string value (even one containing straight numeric data) will be converted to a date/time object for validation as a date value based on the server locale settings, so passing through an ambiguous value of '07/08/2008' will be treated as 7th August 2008 if your server settings are UK, but as 8th July 2008 if your server settings are US. However, if you pass through a value such as '31/12/2008' that would be considered an error by a US-based server, but which is not ambiguous, then PHPExcel will attempt to correct this to 31st December 2008. If the content of the string doesn’t match any of the formats recognised by the php date/time object implementation of strtotime() (which can handle a wider range of formats than the normal strtotime() function), then the function will return a '#VALUE' error. However, Excel recommends that you should always use date/timestamps for your date functions, and the recommendation for PHPExcel is the same: avoid strings because the result is not predictable.
+
+The same principle applies when data is being written to Excel. Cells containing date actual values (rather than Excel functions that return a date value) are always written as Excel dates, converting where necessary. If a cell formatted as a date contains an integer or date/time object value, then it is converted to an Excel value for writing: if a cell formatted as a date contains a real value, then no conversion is required. Note that string values are written as strings rather than converted to Excel date timestamp values.
+
+##### Functions that expect a Date/Time Value
+
+ - DATEDIF
+ - DAY
+ - DAYS360
+ - EDATE
+ - EOMONTH
+ - HOUR
+ - MINUTE
+ - MONTH
+ - NETWORKDAYS
+ - SECOND
+ - WEEKDAY
+ - WEEKNUM
+ - WORKDAY
+ - YEAR
+ - YEARFRAC
+
+#### Helper Methods
+
+In addition to the setExcelCalendar() and getExcelCalendar() methods, a number of other methods are available in the PHPExcel_Shared_Date class that can help when working with dates:
+
+##### PHPExcel_Shared_Date::ExcelToPHP($excelDate)
+
+Converts a date/time from an Excel date timestamp to return a PHP serialized date/timestamp.
+
+Note that this method does not trap for Excel dates that fall outside of the valid range for a PHP date timestamp.
+
+##### PHPExcel_Shared_Date::ExcelToPHPObject($excelDate)
+
+Converts a date from an Excel date/timestamp to return a PHP DateTime object.
+
+##### PHPExcel_Shared_Date::PHPToExcel($PHPDate)
+
+Converts a PHP serialized date/timestamp or a PHP DateTime object to return an Excel date timestamp.
+
+##### PHPExcel_Shared_Date::FormattedPHPToExcel($year, $month, $day, $hours=0, $minutes=0, $seconds=0)
+
+Takes year, month and day values (and optional hour, minute and second values) and returns an Excel date timestamp value.
+
diff --git a/Documentation/markdown/CalculationEngine/FunctionReference/02-General-Introduction.md b/Documentation/markdown/CalculationEngine/FunctionReference/02-General-Introduction.md
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+# Calculation Engine - Formula Function Reference
+
+## General Introduction
+
+### Function that are not Supported in Excel5
+
+Not all functions are supported by the Excel 5 Writer. Use of these functions within your workbooks will result in an error when trying to write to Excel5.
+
+The following is the list of those functions that are implemented within PHPExcel, but that cannot currently be written to Excel 5.
+
+#### Cube Functions
+
+    Excel Function      | Notes
+    --------------------|---------
+	CUBEKPIMEMBER       | Not yet Implemented
+	CUBEMEMBER          | Not yet Implemented
+	CUBEMEMBERPROPERTY  | Not yet Implemented
+	CUBERANKEDMEMBER    | Not yet Implemented
+	CUBESET             | Not yet Implemented
+	CUBESETCOUNT        | Not yet Implemented
+	CUBEVALUE           | Not yet Implemented
+
+
+#### Database Functions
+
+    Excel Function | Notes
+    ---------------|---------
+
+
+#### Date and Time Functions
+
+    Excel Function | Notes
+    ---------------|---------
+    EDATE          | Not a standard function within Excel 5, but an add-in from the Analysis ToolPak.  
+    EOMONTH        | Not a standard function within Excel 5, but an add-in from the Analysis ToolPak.
+
diff --git a/Documentation/markdown/CalculationEngine/FunctionReference/03-01-Cube-Functions.md b/Documentation/markdown/CalculationEngine/FunctionReference/03-01-Cube-Functions.md
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+# Calculation Engine - Formula Function Reference
+
+## Function Reference
+
+### Cube Functions
+
+#### CUBEKPIMEMBER
+
+Not yet implemented.
+
+#### CUBEMEMBER
+
+Not yet implemented.
+
+#### CUBEMEMBERPROPERTY
+
+Not yet implemented.
+
+#### CUBERANKEDMEMBER
+
+Not yet implemented.
+
+#### CUBESET
+
+Not yet implemented.
+
+#### CUBESETCOUNT
+
+Not yet implemented.
+
+#### CUBEVALUE
+
+Not yet implemented.
+
diff --git a/Documentation/markdown/CalculationEngine/FunctionReference/03-02-Database-Functions.md b/Documentation/markdown/CalculationEngine/FunctionReference/03-02-Database-Functions.md
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+# Calculation Engine - Formula Function Reference
+
+## Function Reference
+
+### Database Functions
+
+#### DAVERAGE
+
+The DAVERAGE function returns the average value of the cells in a column of a list or database that match conditions you specify.
+
+##### Syntax
+
+```
+DAVERAGE (database, field, criteria)
+```
+
+##### Parameters
+
+**database** The range of cells that makes up the list or database.  
+
+A database is a list of related data in which rows of related information are records, and columns of data are fields. The first row of the list contains labels for each column.
+
+**field** Indicates which column of the database is used in the function.  
+
+Enter the column label as a string (enclosed between double quotation marks), such as "Age" or "Yield," or as a number (without quotation marks) that represents the position of the column within the list: 1 for the first column, 2 for the second column, and so on.
+
+**criteria** The range of cells that contains the conditions you specify.  
+
+You can use any range for the criteria argument, as long as it includes at least one column label and at least one cell below the column label in which you specify a condition for the column.
+
+##### Return Value
+
+**float** The average value of the matching cells.
+
+This is the statistical mean.
+
+##### Examples
+
+```php
+$database = array( 
+    array( 'Tree',  'Height', 'Age', 'Yield', 'Profit' ),
+    array( 'Apple',  18,       20,    14,      105.00  ),
+    array( 'Pear',   12,       12,    10,       96.00  ),
+    array( 'Cherry', 13,       14,     9,      105.00  ),
+    array( 'Apple',  14,       15,    10,       75.00  ),
+    array( 'Pear',    9,        8,     8,       76.80  ),
+    array( 'Apple',   8,        9,     6,       45.00  ),
+);
+
+$criteria = array( 
+    array( 'Tree',      'Height', 'Age', 'Yield', 'Profit', 'Height' ),
+    array( '="=Apple"', '>10',    NULL,  NULL,    NULL,     '<16'    ),
+    array( '="=Pear"',  NULL,     NULL,  NULL,    NULL,     NULL     ),
+);
+
+$worksheet->fromArray( $criteria, NULL, 'A1' )
+    ->fromArray( $database, NULL, 'A4' );
+
+$worksheet->setCellValue('A12', '=DAVERAGE(A4:E10,"Yield",A1:B2)');
+
+$retVal = $worksheet->getCell('A12')->getCalculatedValue();
+// $retVal = 12
+```
+
+##### Notes
+
+There are no additional notes on this function
+
+#### DCOUNT
+
+The DCOUNT function returns the count of cells that contain a number in a column of a list or database matching conditions that you specify.
+
+##### Syntax
+
+```
+DCOUNT(database, [field], criteria)
+```
+
+##### Parameters
+
+**database** The range of cells that makes up the list or database.  
+
+A database is a list of related data in which rows of related information are records, and columns of data are fields. The first row of the list contains labels for each column.
+
+**field** Indicates which column of the database is used in the function.  
+
+Enter the column label as a string (enclosed between double quotation marks), such as "Age" or "Yield," or as a number (without quotation marks) that represents the position of the column within the list: 1 for the first column, 2 for the second column, and so on.
+
+**criteria** The range of cells that contains the conditions you specify.  
+
+You can use any range for the criteria argument, as long as it includes at least one column label and at least one cell below the column label in which you specify a condition for the column.
+
+##### Return Value
+
+**float**  The count of the matching cells.
+
+##### Examples
+
+```php
+$database = array( 
+    array( 'Tree',  'Height', 'Age', 'Yield', 'Profit' ),
+    array( 'Apple',  18,       20,    14,      105.00  ),
+    array( 'Pear',   12,       12,    10,       96.00  ),
+    array( 'Cherry', 13,       14,     9,      105.00  ),
+    array( 'Apple',  14,       15,    10,       75.00  ),
+    array( 'Pear',    9,        8,     8,       76.80  ),
+    array( 'Apple',   8,        9,     6,       45.00  ),
+);
+
+$criteria = array( 
+    array( 'Tree',      'Height', 'Age', 'Yield', 'Profit', 'Height' ),
+    array( '="=Apple"', '>10',    NULL,  NULL,    NULL,     '<16'    ),
+    array( '="=Pear"',  NULL,     NULL,  NULL,    NULL,     NULL     ),
+);
+
+$worksheet->fromArray( $criteria, NULL, 'A1' )
+    ->fromArray( $database, NULL, 'A4' );
+
+$worksheet->setCellValue('A12', '=DCOUNT(A4:E10,"Height",A1:B3)');
+
+$retVal = $worksheet->getCell('A12')->getCalculatedValue();
+
+// $retVal = 3
+```
+
+##### Notes
+
+In MS Excel, The field argument is optional. If field is omitted, DCOUNT counts all records in the database that match the criteria. This logic has not yet been implemented in PHPExcel.
+
+#### DCOUNTA
+
+The DCOUNT function returns the count of cells that aren’t blank in a column of a list or database and that match conditions that you specify.
+
+##### Syntax
+
+```
+DCOUNTA(database, [field], criteria)
+```
+
+##### Parameters
+
+**database** The range of cells that makes up the list or database.  
+
+A database is a list of related data in which rows of related information are records, and columns of data are fields. The first row of the list contains labels for each column.
+
+**field** Indicates which column of the database is used in the function.  
+
+Enter the column label as a string (enclosed between double quotation marks), such as "Age" or "Yield," or as a number (without quotation marks) that represents the position of the column within the list: 1 for the first column, 2 for the second column, and so on.
+
+**criteria** The range of cells that contains the conditions you specify.  
+
+You can use any range for the criteria argument, as long as it includes at least one column label and at least one cell below the column label in which you specify a condition for the column.
+
+##### Return Value
+
+**float** The count of the matching cells.
+
+##### Examples
+
+```php
+$database = array( 
+    array( 'Tree',  'Height', 'Age', 'Yield', 'Profit' ),
+    array( 'Apple',  18,       20,    14,      105.00  ),
+    array( 'Pear',   12,       12,    10,       96.00  ),
+    array( 'Cherry', 13,       14,     9,      105.00  ),
+    array( 'Apple',  14,       15,    10,       75.00  ),
+    array( 'Pear',    9,        8,     8,       76.80  ),
+    array( 'Apple',   8,        9,     6,       45.00  ),
+);
+
+$criteria = array( 
+    array( 'Tree',      'Height', 'Age', 'Yield', 'Profit', 'Height' ),
+    array( '="=Apple"', '>10',    NULL,  NULL,    NULL,     '<16'    ),
+    array( '="=Pear"',  NULL,     NULL,  NULL,    NULL,     NULL     ),
+);
+
+$worksheet->fromArray( $criteria, NULL, 'A1' )
+    ->fromArray( $database, NULL, 'A4' );
+
+$worksheet->setCellValue('A12', '=DCOUNTA(A4:E10,"Yield",A1:A3)');
+
+$retVal = $worksheet->getCell('A12')->getCalculatedValue();
+
+// $retVal = 5
+```
+
+##### Notes
+
+In MS Excel, The field argument is optional. If field is omitted, DCOUNTA counts all records in the database that match the criteria. This logic has not yet been implemented in PHPExcel.
+
+#### DGET
+
+The DGET function extracts a single value from a column of a list or database that matches conditions that you specify.
+
+##### Syntax
+
+```
+DGET(database, field, criteria)
+```
+
+##### Parameters
+
+**database** The range of cells that makes up the list or database.  
+
+A database is a list of related data in which rows of related information are records, and columns of data are fields. The first row of the list contains labels for each column.
+
+**field** Indicates which column of the database is used in the function.  
+
+Enter the column label as a string (enclosed between double quotation marks), such as "Age" or "Yield," or as a number (without quotation marks) that represents the position of the column within the list: 1 for the first column, 2 for the second column, and so on.
+
+**criteria** The range of cells that contains the conditions you specify.  
+
+You can use any range for the criteria argument, as long as it includes at least one column label and at least one cell below the column label in which you specify a condition for the column.
+
+##### Return Value
+
+**mixed** The value from the selected column of the matching row.
+
+#### Examples
+
+```php
+$database = array( 
+    array( 'Tree',  'Height', 'Age', 'Yield', 'Profit' ),
+    array( 'Apple',  18,       20,    14,      105.00  ),
+    array( 'Pear',   12,       12,    10,       96.00  ),
+    array( 'Cherry', 13,       14,     9,      105.00  ),
+    array( 'Apple',  14,       15,    10,       75.00  ),
+    array( 'Pear',    9,        8,     8,       76.80  ),
+    array( 'Apple',   8,        9,     6,       45.00  ),
+);
+
+$criteria = array( 
+    array( 'Tree',      'Height', 'Age', 'Yield', 'Profit', 'Height' ),
+    array( '="=Apple"', '>10',    NULL,  NULL,    NULL,     '<16'    ),
+    array( '="=Pear"',  NULL,     NULL,  NULL,    NULL,     NULL     ),
+);
+
+$worksheet->fromArray( $criteria, NULL, 'A1' )
+    ->fromArray( $database, NULL, 'A4' );
+
+$worksheet->setCellValue('A12', '=GET(A4:E10,"Age",A1:F2)');
+
+$retVal = $worksheet->getCell('A12')->getCalculatedValue();
+// $retVal = 14
+```
+
+##### Notes
+
+There are no additional notes on this function
+
+#### DMAX
+
+The DMAX function returns the largest number in a column of a list or database that matches conditions you specify.
+
+##### Syntax
+
+```
+DMAX(database, field, criteria)
+```
+
+##### Parameters
+
+**database** The range of cells that makes up the list or database.  
+
+A database is a list of related data in which rows of related information are records, and columns of data are fields. The first row of the list contains labels for each column.
+
+**field** Indicates which column of the database is used in the function.  
+
+Enter the column label as a string (enclosed between double quotation marks), such as "Age" or "Yield," or as a number (without quotation marks) that represents the position of the column within the list: 1 for the first column, 2 for the second column, and so on.
+
+**criteria** The range of cells that contains the conditions you specify.  
+
+You can use any range for the criteria argument, as long as it includes at least one column label and at least one cell below the column label in which you specify a condition for the column.
+
+##### Return Value
+
+**float** The maximum value of the matching cells.
+
+##### Examples
+
+```php
+$database = array( 
+    array( 'Tree',  'Height', 'Age', 'Yield', 'Profit' ),
+    array( 'Apple',  18,       20,    14,      105.00  ),
+    array( 'Pear',   12,       12,    10,       96.00  ),
+    array( 'Cherry', 13,       14,     9,      105.00  ),
+    array( 'Apple',  14,       15,    10,       75.00  ),
+    array( 'Pear',    9,        8,     8,       76.80  ),
+    array( 'Apple',   8,        9,     6,       45.00  ),
+);
+
+$criteria = array( 
+    array( 'Tree',      'Height', 'Age', 'Yield', 'Profit', 'Height' ),
+    array( '="=Apple"', '>10',    NULL,  NULL,    NULL,     '<16'    ),
+    array( '="=Pear"',  NULL,     NULL,  NULL,    NULL,     NULL     ),
+);
+
+$worksheet->fromArray( $criteria, NULL, 'A1' )
+    ->fromArray( $database, NULL, 'A4' );
+
+$worksheet->setCellValue('A12', '=DMAX(A4:E10,"Profit",A1:B2)');
+
+$retVal = $worksheet->getCell('A12')->getCalculatedValue();
+// $retVal = 105
+```
+
+##### Notes
+
+There are no additional notes on this function
+
+#### DMIN
+
+The DMIN function returns the smallest number in a column of a list or database that matches conditions you specify.
+
+##### Syntax
+
+```
+DMIN(database, field, criteria)
+```
+
+##### Parameters
+
+**database** The range of cells that makes up the list or database.  
+
+A database is a list of related data in which rows of related information are records, and columns of data are fields. The first row of the list contains labels for each column.
+
+**field** Indicates which column of the database is used in the function.  
+
+Enter the column label as a string (enclosed between double quotation marks), such as "Age" or "Yield," or as a number (without quotation marks) that represents the position of the column within the list: 1 for the first column, 2 for the second column, and so on.
+
+**criteria**  The range of cells that contains the conditions you specify.  
+
+You can use any range for the criteria argument, as long as it includes at least one column label and at least one cell below the column label in which you specify a condition for the column.
+
+##### Return Value
+
+**float** The minimum value of the matching cells.
+
+##### Examples
+
+```php
+$database = array( 
+    array( 'Tree',  'Height', 'Age', 'Yield', 'Profit' ),
+    array( 'Apple',  18,       20,    14,      105.00  ),
+    array( 'Pear',   12,       12,    10,       96.00  ),
+    array( 'Cherry', 13,       14,     9,      105.00  ),
+    array( 'Apple',  14,       15,    10,       75.00  ),
+    array( 'Pear',    9,        8,     8,       76.80  ),
+    array( 'Apple',   8,        9,     6,       45.00  ),
+);
+
+$criteria = array( 
+    array( 'Tree',      'Height', 'Age', 'Yield', 'Profit', 'Height' ),
+    array( '="=Apple"', '>10',    NULL,  NULL,    NULL,     '<16'    ),
+    array( '="=Pear"',  NULL,     NULL,  NULL,    NULL,     NULL     ),
+);
+
+$worksheet->fromArray( $criteria, NULL, 'A1' )
+    ->fromArray( $database, NULL, 'A4' );
+
+$worksheet->setCellValue('A12', '=DMIN(A4:E10,"Yield",A1:A3)');
+
+$retVal = $worksheet->getCell('A12')->getCalculatedValue();
+// $retVal = 6
+```
+
+##### Notes
+
+There are no additional notes on this function
+
+#### DPRODUCT
+
+The DPRODUCT function multiplies the values in a column of a list or database that match conditions that you specify.
+
+##### Syntax
+
+```
+DPRODUCT(database, field, criteria)
+```
+
+##### Parameters
+
+**database** The range of cells that makes up the list or database.  
+
+A database is a list of related data in which rows of related information are records, and columns of data are fields. The first row of the list contains labels for each column.
+
+**field** Indicates which column of the database is used in the function.  
+
+Enter the column label as a string (enclosed between double quotation marks), such as "Age" or "Yield," or as a number (without quotation marks) that represents the position of the column within the list: 1 for the first column, 2 for the second column, and so on.
+
+**criteria** The range of cells that contains the conditions you specify.  
+
+You can use any range for the criteria argument, as long as it includes at least one column label and at least one cell below the column label in which you specify a condition for the column.
+
+##### Return Value
+
+**float** The product of the matching cells.
+
+##### Examples
+
+```php
+$database = array( 
+    array( 'Tree',  'Height', 'Age', 'Yield', 'Profit' ),
+    array( 'Apple',  18,       20,    14,      105.00  ),
+    array( 'Pear',   12,       12,    10,       96.00  ),
+    array( 'Cherry', 13,       14,     9,      105.00  ),
+    array( 'Apple',  14,       15,    10,       75.00  ),
+    array( 'Pear',    9,        8,     8,       76.80  ),
+    array( 'Apple',   8,        9,     6,       45.00  ),
+);
+
+$criteria = array( 
+    array( 'Tree',      'Height', 'Age', 'Yield', 'Profit', 'Height' ),
+    array( '="=Apple"', '>10',    NULL,  NULL,    NULL,     '<16'    ),
+    array( '="=Pear"',  NULL,     NULL,  NULL,    NULL,     NULL     ),
+);
+
+$worksheet->fromArray( $criteria, NULL, 'A1' )
+    ->fromArray( $database, NULL, 'A4' );
+
+$worksheet->setCellValue('A12', '=DPRODUCT(A4:E10,"Yield",A1:B2)');
+
+$retVal = $worksheet->getCell('A12')->getCalculatedValue();
+// $retVal = 140
+```
+
+##### Notes
+
+There are no additional notes on this function
+
+#### DSTDEV
+
+The DSTDEV function estimates the standard deviation of a population based on a sample by using the numbers in a column of a list or database that match conditions that you specify.
+
+##### Syntax
+
+```
+DSTDEV(database, field, criteria)
+```
+
+##### Parameters
+
+**database** The range of cells that makes up the list or database.  
+
+A database is a list of related data in which rows of related information are records, and columns of data are fields. The first row of the list contains labels for each column.
+
+**field** Indicates which column of the database is used in the function.  
+
+Enter the column label as a string (enclosed between double quotation marks), such as "Age" or "Yield," or as a number (without quotation marks) that represents the position of the column within the list: 1 for the first column, 2 for the second column, and so on.
+
+**criteria** The range of cells that contains the conditions you specify.  
+
+You can use any range for the criteria argument, as long as it includes at least one column label and at least one cell below the column label in which you specify a condition for the column.
+
+##### Return Value
+
+**float** The estimated standard deviation of the matching cells.
+
+##### Examples
+
+```php
+$database = array( 
+    array( 'Tree',  'Height', 'Age', 'Yield', 'Profit' ),
+    array( 'Apple',  18,       20,    14,      105.00  ),
+    array( 'Pear',   12,       12,    10,       96.00  ),
+    array( 'Cherry', 13,       14,     9,      105.00  ),
+    array( 'Apple',  14,       15,    10,       75.00  ),
+    array( 'Pear',    9,        8,     8,       76.80  ),
+    array( 'Apple',   8,        9,     6,       45.00  ),
+);
+
+$criteria = array( 
+    array( 'Tree',      'Height', 'Age', 'Yield', 'Profit', 'Height' ),
+    array( '="=Apple"', '>10',    NULL,  NULL,    NULL,     '<16'    ),
+    array( '="=Pear"',  NULL,     NULL,  NULL,    NULL,     NULL     ),
+);
+
+$worksheet->fromArray( $criteria, NULL, 'A1' )
+    ->fromArray( $database, NULL, 'A4' );
+
+$worksheet->setCellValue('A12', '=DSTDEV(A4:E10,"Yield",A1:A3)');
+
+$retVal = $worksheet->getCell('A12')->getCalculatedValue();
+// $retVal = 2.97
+```
+
+##### Notes
+
+There are no additional notes on this function
+
+#### DSTDEVP
+
+The DSTDEVP function calculates the standard deviation of a population based on the entire population by using the numbers in a column of a list or database that match conditions that you specify.
+
+##### Syntax
+
+```
+DSTDEVP(database, field, criteria)
+```
+
+##### Parameters
+
+**database** The range of cells that makes up the list or database.  
+
+A database is a list of related data in which rows of related information are records, and columns of data are fields. The first row of the list contains labels for each column.
+
+**field** Indicates which column of the database is used in the function.  
+
+Enter the column label as a string (enclosed between double quotation marks), such as "Age" or "Yield," or as a number (without quotation marks) that represents the position of the column within the list: 1 for the first column, 2 for the second column, and so on.
+
+**criteria** The range of cells that contains the conditions you specify.  
+
+You can use any range for the criteria argument, as long as it includes at least one column label and at least one cell below the column label in which you specify a condition for the column.
+
+##### Return Value
+
+**float** The estimated standard deviation of the matching cells.
+
+##### Examples
+
+```php
+$database = array( 
+    array( 'Tree',  'Height', 'Age', 'Yield', 'Profit' ),
+    array( 'Apple',  18,       20,    14,      105.00  ),
+    array( 'Pear',   12,       12,    10,       96.00  ),
+    array( 'Cherry', 13,       14,     9,      105.00  ),
+    array( 'Apple',  14,       15,    10,       75.00  ),
+    array( 'Pear',    9,        8,     8,       76.80  ),
+    array( 'Apple',   8,        9,     6,       45.00  ),
+);
+
+$criteria = array( 
+    array( 'Tree',      'Height', 'Age', 'Yield', 'Profit', 'Height' ),
+    array( '="=Apple"', '>10',    NULL,  NULL,    NULL,     '<16'    ),
+    array( '="=Pear"',  NULL,     NULL,  NULL,    NULL,     NULL     ),
+);
+
+$worksheet->fromArray( $criteria, NULL, 'A1' )
+    ->fromArray( $database, NULL, 'A4' );
+
+$worksheet->setCellValue('A12', '=DSTDEVP(A4:E10,"Yield",A1:A3)');
+
+$retVal = $worksheet->getCell('A12')->getCalculatedValue();
+// $retVal = 2.65
+```
+
+##### Notes
+
+There are no additional notes on this function
+
+#### DSUM
+
+The DSUM function adds the numbers in a column of a list or database that matches conditions you specify.
+
+##### Syntax
+
+```
+DSUM(database, field, criteria)
+```
+
+##### Parameters
+
+**database** The range of cells that makes up the list or database.  
+
+A database is a list of related data in which rows of related information are records, and columns of data are fields. The first row of the list contains labels for each column.
+
+**field** Indicates which column of the database is used in the function.  
+
+Enter the column label as a string (enclosed between double quotation marks), such as "Age" or "Yield," or as a number (without quotation marks) that represents the position of the column within the list: 1 for the first column, 2 for the second column, and so on.
+
+**criteria** The range of cells that contains the conditions you specify.  
+
+You can use any range for the criteria argument, as long as it includes at least one column label and at least one cell below the column label in which you specify a condition for the column.
+
+##### Return Value
+
+**float** The total value of the matching cells.
+
+##### Examples
+
+```php
+$database = array( 
+    array( 'Tree',  'Height', 'Age', 'Yield', 'Profit' ),
+    array( 'Apple',  18,       20,    14,      105.00  ),
+    array( 'Pear',   12,       12,    10,       96.00  ),
+    array( 'Cherry', 13,       14,     9,      105.00  ),
+    array( 'Apple',  14,       15,    10,       75.00  ),
+    array( 'Pear',    9,        8,     8,       76.80  ),
+    array( 'Apple',   8,        9,     6,       45.00  ),
+);
+
+$criteria = array( 
+    array( 'Tree',      'Height', 'Age', 'Yield', 'Profit', 'Height' ),
+    array( '="=Apple"', '>10',    NULL,  NULL,    NULL,     '<16'    ),
+    array( '="=Pear"',  NULL,     NULL,  NULL,    NULL,     NULL     ),
+);
+
+$worksheet->fromArray( $criteria, NULL, 'A1' )
+    ->fromArray( $database, NULL, 'A4' );
+
+$worksheet->setCellValue('A12', '=DMIN(A4:E10,"Profit",A1:A2)');
+
+$retVal = $worksheet->getCell('A12')->getCalculatedValue();
+// $retVal = 225
+```
+
+##### Notes
+
+There are no additional notes on this function
+
+#### DVAR
+
+Not yet documented.
+
+#### DVARP
+
+Not yet documented.
+
diff --git a/Documentation/markdown/CalculationEngine/FunctionReference/03-03-Date-and-Time-Functions.md b/Documentation/markdown/CalculationEngine/FunctionReference/03-03-Date-and-Time-Functions.md
new file mode 100644
index 0000000..d0cc568
--- /dev/null
+++ b/Documentation/markdown/CalculationEngine/FunctionReference/03-03-Date-and-Time-Functions.md
@@ -0,0 +1,1000 @@
+# Calculation Engine - Formula Function Reference
+
+## Function Reference
+
+### Date and Time Functions
+
+Excel provides a number of functions for the manipulation of dates and times, and calculations based on date/time values. it is worth spending some time reading the section titled "Date and Time Values" on passing date parameters and returning date values to understand how PHPExcel reconciles the differences between dates and times in Excel and in PHP.
+
+#### DATE
+
+The DATE function returns an Excel timestamp or a PHP timestamp or date object representing the date that is referenced by the parameters.
+
+##### Syntax
+
+```
+DATE(year, month, day)
+```
+
+##### Parameters
+
+**year** The year number.  
+
+If this value is between 0 (zero) and 1899 inclusive (for the Windows 1900 calendar), or between 4 and 1903 inclusive (for the Mac 1904), then PHPExcel adds it to the Calendar base year, so a value of 108 will interpret the year as 2008 when using the Windows 1900 calendar, or 2012 when using the Mac 1904 calendar.
+
+**month** The month number.  
+
+If this value is greater than 12, the DATE function adds that number of months to the first month in the year specified. For example, DATE(2008,14,2) returns a value representing February 2, 2009.
+
+If the value of __month__ is less than 1, then that value will be adjusted by -1, and that will then be subtracted from the first month of the year specified. For example, DATE(2008,0,2) returns a value representing December 2, 2007; while DATE(2008,-1,2) returns a value representing November 2, 2007.
+
+**day** The day number.  
+
+If this value is greater than the number of days in the month (and year) specified, the DATE function adds that number of days to the first day in the month. For example, DATE(2008,1,35) returns a value representing February 4, 2008.
+
+If the value of __day__ is less than 1, then that value will be adjusted by -1, and that will then be subtracted from the first month of the year specified. For example, DATE(2008,3,0) returns a value representing February 29, 2008; while DATE(2008,3,-2) returns a value representing February 27, 2008.
+
+##### Return Value
+
+**mixed** A date/time stamp that corresponds to the given date.  
+
+This could be a PHP timestamp value (integer), a PHP date/time object, or an Excel timestamp value (real), depending on the value of PHPExcel_Calculation_Functions::getReturnDateType().
+
+##### Examples
+
+```php
+$worksheet->setCellValue('A1', 'Year')
+    ->setCellValue('A2', 'Month')
+    ->setCellValue('A3', 'Day');
+
+$worksheet->setCellValue('B1', 2008)
+    ->setCellValue('B2', 12)
+    ->setCellValue('B3', 31);
+
+$worksheet->setCellValue('D1', '=DATE(B1,B2,B3)');
+
+$retVal = $worksheet->getCell('D1')->getCalculatedValue();
+// $retVal = 1230681600
+```
+
+```php
+// We're going to be calling the same cell calculation multiple times,
+//    and expecting different return values, so disable calculation cacheing
+PHPExcel_Calculation::getInstance()->setCalculationCacheEnabled(FALSE);
+
+$saveFormat = PHPExcel_Calculation_Functions::getReturnDateType();
+
+PHPExcel_Calculation_Functions::setReturnDateType(
+    PHPExcel_Calculation_Functions::RETURNDATE_EXCEL
+);
+
+$retVal = call_user_func_array(
+    array('PHPExcel_Calculation_Functions', 'DATE'),
+    array(2008, 12, 31)
+);
+// $retVal = 39813.0
+
+PHPExcel_Calculation_Functions::setReturnDateType(
+    PHPExcel_Calculation_Functions::RETURNDATE_PHP_NUMERIC
+);
+
+$retVal = call_user_func_array(
+    array('PHPExcel_Calculation_Functions', 'DATE'),
+    array(2008, 12, 31)
+);
+// $retVal = 1230681600
+
+PHPExcel_Calculation_Functions::setReturnDateType($saveFormat);
+```
+
+##### Notes
+
+There are no additional notes on this function
+
+#### DATEDIF
+
+The DATEDIF function computes the difference between two dates in a variety of different intervals, such number of years, months, or days.
+
+##### Syntax
+
+```
+DATEDIF(date1, date2 [, unit])
+```
+
+##### Parameters
+
+**date1** First Date.  
+
+An Excel date value, PHP date timestamp, PHP date object, or a date represented as a string.
+
+**date2** Second Date.  
+
+An Excel date value, PHP date timestamp, PHP date object, or a date represented as a string.
+
+**unit** The interval type to use for the calculation  
+
+This is a string, comprising one of the values listed below:
+
+Unit | Meaning                         | Description
+-----|---------------------------------|--------------------------------
+m    | Months                          | Complete calendar months between the dates.
+d    | Days                            | Number of days between the dates.
+y    | Years                           | Complete calendar years between the dates.
+ym   | Months Excluding Years          | Complete calendar months between the dates as if they were of the same year.
+yd   | Days Excluding Years            | Complete calendar days between the dates as if they were of the same year.
+md   | Days Excluding Years And Months | Complete calendar days between the dates as if they were of the same month and same year.
+
+The unit value is not case sensitive, and defaults to "d".
+
+##### Return Value
+
+**integer** An integer value that reflects the difference between the two dates.  
+
+This could be the number of full days, months or years between the two dates, depending on the interval unit value passed into the function as the third parameter.
+
+##### Examples
+
+```php
+$worksheet->setCellValue('A1', 'Year')
+    ->setCellValue('A2', 'Month')
+    ->setCellValue('A3', 'Day');
+
+$worksheet->setCellValue('B1', 2001)
+    ->setCellValue('C1', 2009)
+    ->setCellValue('B2', 7)
+    ->setCellValue('C2', 12)
+    ->setCellValue('B3', 1)
+    ->setCellValue('C3', 31);
+
+$worksheet->setCellValue('D1', '=DATEDIF(DATE(B1,B2,B3),DATE(C1,C2,C3),"d")')
+    ->setCellValue('D2', '=DATEDIF(DATE(B1,B2,B3),DATE(C1,C2,C3),"m")')
+    ->setCellValue('D3', '=DATEDIF(DATE(B1,B2,B3),DATE(C1,C2,C3),"y")')
+    ->setCellValue('D4', '=DATEDIF(DATE(B1,B2,B3),DATE(C1,C2,C3),"ym")')
+    ->setCellValue('D5', '=DATEDIF(DATE(B1,B2,B3),DATE(C1,C2,C3),"yd")')
+    ->setCellValue('D6', '=DATEDIF(DATE(B1,B2,B3),DATE(C1,C2,C3),"md")');
+
+$retVal = $worksheet->getCell('D1')->getCalculatedValue();
+// $retVal = 3105
+
+$retVal = $worksheet->getCell('D2')->getCalculatedValue();
+// $retVal = 101
+
+$retVal = $worksheet->getCell('D3')->getCalculatedValue();
+// $retVal = 8
+
+$retVal = $worksheet->getCell('D4')->getCalculatedValue();
+// $retVal = 5
+
+$retVal = $worksheet->getCell('D5')->getCalculatedValue();
+// $retVal = 183
+
+$retVal = $worksheet->getCell('D6')->getCalculatedValue();
+// $retVal = 30
+```
+
+```php
+$date1 = 1193317015; // PHP timestamp for 25-Oct-2007
+$date2 = 1449579415; // PHP timestamp for 8-Dec-2015
+
+$retVal = call_user_func_array(
+    array('PHPExcel_Calculation_Functions', 'DATEDIF'),
+    array($date1, $date2, 'd')
+);
+// $retVal = 2966
+
+$retVal = call_user_func_array(
+    array('PHPExcel_Calculation_Functions', 'DATEDIF'),
+    array($date1, $date2, 'm')
+);
+// $retVal = 97
+
+$retVal = call_user_func_array(
+    array('PHPExcel_Calculation_Functions', 'DATEDIF'),
+    array($date1, $date2, 'y')
+);
+// $retVal = 8
+
+$retVal = call_user_func_array(
+    array('PHPExcel_Calculation_Functions', 'DATEDIF'),
+    array($date1, $date2, 'ym')
+);
+// $retVal = 1
+
+$retVal = call_user_func_array(
+    array('PHPExcel_Calculation_Functions', 'DATEDIF'),
+    array($date1, $date2, 'yd')
+);
+// $retVal = 44
+
+$retVal = call_user_func_array(
+    array('PHPExcel_Calculation_Functions', 'DATEDIF'),
+    array($date1, $date2, 'md')
+);
+// $retVal = 13
+```
+
+##### Notes
+
+If Date1 is later than Date2, DATEDIF will return a #NUM! error.
+
+#### DATEVALUE
+
+The DATEVALUE function returns the date represented by a date formatted as a text string. Use DATEVALUE to convert a date represented by text to a serial number.
+
+##### Syntax
+
+```
+DATEVALUE(dateString)
+```
+
+##### Parameters
+
+**date** Date String.  
+
+A string, representing a date value.
+
+##### Return Value
+
+**mixed** A date/time stamp that corresponds to the given date.  
+
+This could be a PHP timestamp value (integer), a PHP date/time object, or an Excel timestamp value (real), depending on the value of PHPExcel_Calculation_Functions::getReturnDateType().
+
+##### Examples
+
+```php
+$worksheet->setCellValue('A1', 'Date String');
+    ->setCellValue('A2', '31-Dec-2008')
+    ->setCellValue('A3', '31/12/2008')
+    ->setCellValue('A4', '12-31-2008');
+
+$worksheet->setCellValue('B2', '=DATEVALUE(A2)')
+    ->setCellValue('B3', '=DATEVALUE(A3)')
+    ->setCellValue('B4', '=DATEVALUE(A4)');
+
+PHPExcel_Calculation_Functions::setReturnDateType(
+    PHPExcel_Calculation_Functions::RETURNDATE_EXCEL
+);
+
+$retVal = $worksheet->getCell('B2')->getCalculatedValue();
+
+$retVal = $worksheet->getCell('B3')->getCalculatedValue();
+
+$retVal = $worksheet->getCell('B4')->getCalculatedValue();
+// $retVal = 39813.0 for all cases
+```
+
+```php
+// We're going to be calling the same cell calculation multiple times,
+//    and expecting different return values, so disable calculation cacheing
+PHPExcel_Calculation::getInstance()->setCalculationCacheEnabled(FALSE);
+
+$saveFormat = PHPExcel_Calculation_Functions::getReturnDateType();
+
+PHPExcel_Calculation_Functions::setReturnDateType(
+    PHPExcel_Calculation_Functions::RETURNDATE_EXCEL
+);
+
+$retVal = call_user_func_array(
+    array('PHPExcel_Calculation_Functions', 'DATEVALUE'),
+    array('31-Dec-2008')
+);
+// $retVal = 39813.0
+
+PHPExcel_Calculation_Functions::setReturnDateType(
+    PHPExcel_Calculation_Functions::RETURNDATE_PHP_NUMERIC
+);
+
+$retVal = call_user_func_array(
+    array('PHPExcel_Calculation_Functions', 'DATEVALUE'),
+    array('31-Dec-2008')
+);
+// $retVal = 1230681600
+
+PHPExcel_Calculation_Functions::setReturnDateType($saveFormat);
+```
+
+##### Notes
+
+DATEVALUE uses the php date/time object implementation of strtotime() (which can handle a wider range of formats than the normal strtotime() function), and it is also called for any date parameter passed to other date functions (such as DATEDIF) when the parameter value is a string.
+
+__WARNING:-__ PHPExcel accepts a wider range of date formats than MS Excel, so it is entirely possible that Excel will return a #VALUE! error when passed a date string that it can’t interpret, while PHPExcel is able to translate that same string into a correct date value.
+
+Care should be taken in workbooks that use string formatted dates in calculations when writing to Excel5 or Excel2007.
+
+#### DAY
+
+The DAY function returns the day of a date. The day is given as an integer ranging from 1 to 31.
+
+##### Syntax
+
+```
+DAY(datetime)
+```
+
+##### Parameters
+
+**datetime** Date. 
+
+An Excel date value, PHP date timestamp, PHP date object, or a date represented as a string.
+
+##### Return Value
+
+**integer** An integer value that reflects the day of the month.
+
+This is an integer ranging from 1 to 31.
+
+##### Examples
+
+```php
+$worksheet->setCellValue('A1', 'Date String')
+    ->setCellValue('A2', '31-Dec-2008')
+    ->setCellValue('A3', '14-Feb-2008');
+
+$worksheet->setCellValue('B2', '=DAY(A2)')
+    ->setCellValue('B3', '=DAY(A3)');
+
+$retVal = $worksheet->getCell('B2')->getCalculatedValue();
+// $retVal = 31
+
+$retVal = $worksheet->getCell('B3')->getCalculatedValue();
+// $retVal = 14
+```
+
+```php
+$retVal = call_user_func_array(
+    array('PHPExcel_Calculation_Functions', 'DAYOFMONTH'),
+    array('25-Dec-2008')
+);
+// $retVal = 25
+```
+
+##### Notes
+
+Note that the PHPExcel function is PHPExcel_Calculation_Functions::DAYOFMONTH() when the method is called statically.
+
+#### DAYS360
+
+The DAYS360 function computes the difference between two dates based on a 360 day year (12 equal periods of 30 days each) used by some accounting systems.
+
+##### Syntax
+
+```
+DAYS360(date1, date2 [, method])
+```
+
+#### Parameters
+
+**date1** First Date.  
+
+An Excel date value, PHP date timestamp, PHP date object, or a date represented as a string.
+
+**date2** Second Date.  
+
+An Excel date value, PHP date timestamp, PHP date object, or a date represented as a string.
+
+**method** A boolean flag (TRUE or FALSE)
+
+This is a flag that determines which method to use in the calculation, based on the values listed below:
+
+    method | Description
+    -------|------------
+    FALSE  | U.S. (NASD) method. If the starting date is the last day of a month, it becomes equal to the 30th of the same month. If the ending date is the last day of a month and the starting date is earlier than the 30th of a month, the ending date becomes equal to the 1st of the next month; otherwise the ending date becomes equal to the 30th of the same month.
+    TRUE   | European method. Starting dates and ending dates that occur on the 31st of a month become equal to the 30th of the same month.
+
+The method value defaults to FALSE.
+
+##### Return Value
+
+**integer** An integer value that reflects the difference between the two dates.
+
+This is the number of full days between the two dates, based on a 360 day year.
+
+##### Examples
+
+```php
+$worksheet->setCellValue('B1', 'Start Date')
+    ->setCellValue('C1', 'End Date')
+    ->setCellValue('A2', 'Year')
+    ->setCellValue('A3', 'Month')
+    ->setCellValue('A4', 'Day');
+
+$worksheet->setCellValue('B2', 2003)
+    ->setCellValue('B3', 2)
+    ->setCellValue('B4', 3);
+
+$worksheet->setCellValue('C2', 2007)
+    ->setCellValue('C3', 5)
+    ->setCellValue('C4', 31);
+
+$worksheet->setCellValue('E2', '=DAYS360(DATE(B2,B3,B4),DATE(C2,C3,C4))')
+    ->setCellValue('E4', '=DAYS360(DATE(B2,B3,B4),DATE(C2,C3,C4),FALSE)');
+
+$retVal = $worksheet->getCell('E2')->getCalculatedValue();
+// $retVal = 1558
+
+$retVal = $worksheet->getCell('E4')->getCalculatedValue();
+// $retVal = 1557
+```
+
+```php
+$date1 = 37655.0; // Excel timestamp for 25-Oct-2007
+$date2 = 39233.0; // Excel timestamp for 8-Dec-2015
+
+$retVal = call_user_func_array(
+    array('PHPExcel_Calculation_Functions', 'DAYS360'),
+    array($date1, $date2)
+);
+// $retVal = 1558
+
+$retVal = call_user_func_array(
+    array('PHPExcel_Calculation_Functions', 'DAYS360'),
+    array($date1, $date2, TRUE)
+);
+// $retVal = 1557
+```
+
+##### Notes
+
+__WARNING:-__ This function does not currently work with the Excel5 Writer when a PHP Boolean is used for the third (optional) parameter (as shown in the example above), and the writer will generate and error. It will work if a numeric 0 or 1 is used for the method parameter; or if the Excel TRUE() and FALSE() functions are used instead.
+
+#### EDATE
+
+The EDATE function returns an Excel timestamp or a PHP timestamp or date object representing the date that is the indicated number of months before or after a specified date (the start_date). Use EDATE to calculate maturity dates or due dates that fall on the same day of the month as the date of issue.
+
+##### Syntax
+
+```
+EDATE(baseDate, months)
+```
+
+##### Parameters
+
+**baseDate** Start Date.
+
+An Excel date value, PHP date timestamp, PHP date object, or a date represented as a string.
+
+**months** Number of months to add.
+
+An integer value indicating the number of months before or after baseDate. A positive value for months yields a future date; a negative value yields a past date.
+
+##### Return Value
+
+**mixed** A date/time stamp that corresponds to the basedate + months.
+
+This could be a PHP timestamp value (integer), a PHP date/time object, or an Excel timestamp value (real), depending on the value of PHPExcel_Calculation_Functions::getReturnDateType().
+
+##### Examples
+
+```php
+$worksheet->setCellValue('A1', 'Date String')
+    ->setCellValue('A2', '1-Jan-2008')
+    ->setCellValue('A3', '29-Feb-2008');
+
+$worksheet->setCellValue('B2', '=EDATE(A2,5)')
+    ->setCellValue('B3', '=EDATE(A3,-12)');
+
+PHPExcel_Calculation_Functions::setReturnDateType(
+    PHPExcel_Calculation_Functions::RETURNDATE_EXCEL
+);
+
+$retVal = $worksheet->getCell('B2')->getCalculatedValue();
+// $retVal = 39600.0 (1-Jun-2008)
+
+$retVal = $worksheet->getCell('B3')->getCalculatedValue();
+// $retVal = 39141.0 (28-Feb-2007)
+```
+
+```php
+PHPExcel_Calculation_Functions::setReturnDateType(
+    PHPExcel_Calculation_Functions::RETURNDATE_EXCEL
+);
+
+$retVal = call_user_func_array(
+    array('PHPExcel_Calculation_Functions', 'EDATE'),
+    array('31-Oct-2008',25)
+);
+// $retVal = 40512.0 (30-Nov-2010)
+```
+
+###### Notes
+
+__WARNING:-__ This function is currently not supported by the Excel5 Writer because it is not a standard function within Excel 5, but an add-in from the Analysis ToolPak.
+
+#### EOMONTH
+
+The EOMONTH function returns an Excel timestamp or a PHP timestamp or date object representing the date of the last day of the month that is the indicated number of months before or after a specified date (the start_date). Use EOMONTH to calculate maturity dates or due dates that fall on the last day of the month.
+
+##### Syntax
+
+```
+EOMONTH(baseDate, months)
+```
+
+##### Parameters
+
+**baseDate** Start Date.
+
+An Excel date value, PHP date timestamp, PHP date object, or a date represented as a string.
+
+**months** Number of months to add.
+
+An integer value indicating the number of months before or after baseDate. A positive value for months yields a future date; a negative value yields a past date.
+
+##### Return Value
+
+**mixed** A date/time stamp that corresponds to the last day of basedate + months.
+
+This could be a PHP timestamp value (integer), a PHP date/time object, or an Excel timestamp value (real), depending on the value of PHPExcel_Calculation_Functions::getReturnDateType().
+
+##### Examples
+
+```php
+$worksheet->setCellValue('A1', 'Date String')
+    ->setCellValue('A2', '1-Jan-2000')
+    ->setCellValue('A3', '14-Feb-2009');
+
+$worksheet->setCellValue('B2', '=EOMONTH(A2,5)')
+    ->setCellValue('B3', '=EOMONTH(A3,-12)');
+
+PHPExcel_Calculation_Functions::setReturnDateType(PHPExcel_Calculation_Functions::RETURNDATE_EXCEL);
+
+$retVal = $worksheet->getCell('B2')->getCalculatedValue();
+// $retVal = 39629.0 (30-Jun-2008)
+
+$retVal = $worksheet->getCell('B3')->getCalculatedValue();
+// $retVal = 39507.0 (29-Feb-2008)
+```
+
+```php
+PHPExcel_Calculation_Functions::setReturnDateType(
+    PHPExcel_Calculation_Functions::RETURNDATE_EXCEL
+);
+
+$retVal = call_user_func_array(
+    array('PHPExcel_Calculation_Functions', 'EOMONTH'),
+    array('31-Oct-2008',13)
+);
+// $retVal = 40147.0 (30-Nov-2010)
+```
+
+##### Notes
+
+__WARNING:-__ This function is currently not supported by the Excel5 Writer because it is not a standard function within Excel 5, but an add-in from the Analysis ToolPak.
+
+#### HOUR
+
+The HOUR function returns the hour of a time value. The hour is given as an integer, ranging from 0 (12:00 A.M.) to 23 (11:00 P.M.).
+
+##### Syntax
+
+```
+HOUR(datetime)
+```
+
+##### Parameters
+
+**datetime** Time.
+
+An Excel date/time value, PHP date timestamp, PHP date object, or a date/time represented as a string.
+
+##### Return Value
+
+**integer** An integer value that reflects the hour of the day.
+
+This is an integer ranging from 0 to 23.
+
+##### Examples
+
+```php
+$worksheet->setCellValue('A1', 'Time String')
+    ->setCellValue('A2', '31-Dec-2008 17:30')
+    ->setCellValue('A3', '14-Feb-2008 4:20 AM')
+    ->setCellValue('A4', '14-Feb-2008 4:20 PM');
+
+$worksheet->setCellValue('B2', '=HOUR(A2)')
+    ->setCellValue('B3', '=HOUR(A3)')
+    ->setCellValue('B4', '=HOUR(A4)');
+
+$retVal = $worksheet->getCell('B2')->getCalculatedValue();
+// $retVal = 17
+
+$retVal = $worksheet->getCell('B3')->getCalculatedValue();
+// $retVal = 4
+
+$retVal = $worksheet->getCell('B4')->getCalculatedValue();
+// $retVal = 16
+```
+
+```php
+$retVal = call_user_func_array(
+    array('PHPExcel_Calculation_Functions', 'HOUROFDAY'),
+    array('09:30')
+);
+// $retVal = 9
+```
+
+##### Notes
+
+Note that the PHPExcel function is PHPExcel_Calculation_Functions::HOUROFDAY() when the method is called statically.
+
+#### MINUTE
+
+The MINUTE function returns the minutes of a time value. The minute is given as an integer, ranging from 0 to 59.
+
+##### Syntax
+
+```
+MINUTE(datetime)
+```
+
+##### Parameters
+
+**datetime** Time.
+
+An Excel date/time value, PHP date timestamp, PHP date object, or a date/time represented as a string.
+
+##### Return Value
+
+**integer** An integer value that reflects the minutes within the hour.
+
+This is an integer ranging from 0 to 59.
+
+##### Examples
+
+```php
+$worksheet->setCellValue('A1', 'Time String')
+    ->setCellValue('A2', '31-Dec-2008 17:30')
+    ->setCellValue('A3', '14-Feb-2008 4:20 AM')
+    ->setCellValue('A4', '14-Feb-2008 4:45 PM');
+
+$worksheet->setCellValue('B2', '=MINUTE(A2)')
+    ->setCellValue('B3', '=MINUTE(A3)')
+    ->setCellValue('B4', '=MINUTE(A4)');
+
+$retVal = $worksheet->getCell('B2')->getCalculatedValue();
+// $retVal = 30
+
+$retVal = $worksheet->getCell('B3')->getCalculatedValue();
+// $retVal = 20
+
+$retVal = $worksheet->getCell('B4')->getCalculatedValue();
+// $retVal = 45
+```
+
+```php
+$retVal = call_user_func_array(
+    array('PHPExcel_Calculation_Functions', 'MINUTEOFHOUR'),
+    array('09:30')
+);
+// $retVal = 30
+```
+
+##### Notes
+
+Note that the PHPExcel function is PHPExcel_Calculation_Functions::MINUTEOFHOUR() when the method is called statically.
+
+#### MONTH
+
+The MONTH function returns the month of a date. The month is given as an integer ranging from 1 to 12.
+
+##### Syntax
+
+```
+MONTH(datetime)
+```
+
+##### Parameters
+
+**datetime** Date.
+
+An Excel date value, PHP date timestamp, PHP date object, or a date represented as a string.
+
+##### Return Value
+
+**integer** An integer value that reflects the month of the year.
+
+This is an integer ranging from 1 to 12.
+
+##### Examples
+
+```php
+$worksheet->setCellValue('A1', 'Date String');
+$worksheet->setCellValue('A2', '31-Dec-2008');
+$worksheet->setCellValue('A3', '14-Feb-2008');
+
+$worksheet->setCellValue('B2', '=MONTH(A2)');
+$worksheet->setCellValue('B3', '=MONTH(A3)');
+
+$retVal = $worksheet->getCell('B2')->getCalculatedValue();
+// $retVal = 12
+
+$retVal = $worksheet->getCell('B3')->getCalculatedValue();
+// $retVal = 2
+```
+
+```php
+$retVal = call_user_func_array(
+    array('PHPExcel_Calculation_Functions', 'MONTHOFYEAR'),
+    array('14-July-2008')
+);
+// $retVal = 7
+```
+
+#### Notes
+
+Note that the PHPExcel function is PHPExcel_Calculation_Functions::MONTHOFYEAR() when the method is called statically.
+
+#### NETWORKDAYS
+
+The NETWORKDAYS function returns the number of whole working days between a *start date* and an *end date*. Working days exclude weekends and any dates identified in *holidays*. Use NETWORKDAYS to calculate employee benefits that accrue based on the number of days worked during a specific term.
+
+##### Syntax
+
+```
+NETWORKDAYS(startDate, endDate [, holidays])
+```
+
+##### Parameters
+
+**startDate** Start Date of the period.
+
+An Excel date value, PHP date timestamp, PHP date object, or a date represented as a string.
+
+**endDate** End Date of the period.
+
+An Excel date value, PHP date timestamp, PHP date object, or a date represented as a string.
+
+**holidays** Optional array of Holiday dates.
+
+An optional range of one or more dates to exclude from the working calendar, such as state and federal holidays and floating holidays.
+
+The list can be either a range of cells that contains the dates or an array constant of Excel date values, PHP date timestamps, PHP date objects, or dates represented as strings.
+
+##### Return Value
+
+**integer** Number of working days.
+
+The number of working days between startDate and endDate.
+
+##### Examples
+
+```php
+```
+
+```php
+```
+
+##### Notes
+
+There are no additional notes on this function
+
+#### NOW
+
+The NOW function returns the current date and time.
+
+##### Syntax
+
+```
+NOW()
+```
+
+##### Parameters
+
+There are now parameters for the NOW() function.
+
+##### Return Value
+
+**mixed** A date/time stamp that corresponds to the current date and time.
+
+This could be a PHP timestamp value (integer), a PHP date/time object, or an Excel timestamp value (real), depending on the value of PHPExcel_Calculation_Functions::getReturnDateType().
+
+##### Examples
+
+```php
+```
+
+```php
+```
+
+##### Notes
+
+Note that the PHPExcel function is PHPExcel_Calculation_Functions::DATETIMENOW() when the method is called statically.
+
+#### SECOND
+
+The SECOND function returns the seconds of a time value. The second is given as an integer, ranging from 0 to 59.
+
+##### Syntax
+
+```
+SECOND(datetime)
+```
+
+##### Parameters
+
+**datetime** Time.
+
+An Excel date/time value, PHP date timestamp, PHP date object, or a date/time represented as a string.
+
+##### Return Value
+
+**integer** An integer value that reflects the seconds within the minute.
+
+This is an integer ranging from 0 to 59.
+
+##### Examples
+
+```php
+$worksheet->setCellValue('A1', 'Time String')
+    ->setCellValue('A2', '31-Dec-2008 17:30:20')
+    ->setCellValue('A3', '14-Feb-2008 4:20 AM')
+    ->setCellValue('A4', '14-Feb-2008 4:45:59 PM');
+
+$worksheet->setCellValue('B2', '=SECOND(A2)')
+    ->setCellValue('B3', '=SECOND(A3)');
+    ->setCellValue('B4', '=SECOND(A4)');
+
+$retVal = $worksheet->getCell('B2')->getCalculatedValue();
+// $retVal = 20
+
+$retVal = $worksheet->getCell('B3')->getCalculatedValue();
+// $retVal = 0
+
+$retVal = $worksheet->getCell('B4')->getCalculatedValue();
+// $retVal = 59
+```
+
+```php
+$retVal = call_user_func_array(
+    array('PHPExcel_Calculation_Functions', 'SECONDOFMINUTE'),
+    array('09:30:17')
+);
+// $retVal = 17
+```
+
+##### Notes
+
+Note that the PHPExcel function is PHPExcel_Calculation_Functions::SECONDOFMINUTE() when the method is called statically.
+
+#### TIME
+
+Not yet documented.
+
+#### TIMEVALUE
+
+Not yet documented.
+
+#### TODAY
+
+Not yet documented.
+
+#### WEEKDAY
+
+The WEEKDAY function returns the day of the week for a given date. The day is given as an integer ranging from 1 to 7, although this can be modified to return a value between 0 and 6.
+
+##### Syntax
+
+```
+WEEKDAY(datetime [, method])
+```
+
+##### Parameters
+
+**datetime** Date.
+
+An Excel date value, PHP date timestamp, PHP date object, or a date represented as a string.
+
+**method** An integer flag (values 0, 1 or 2)
+
+This is a flag that determines which method to use in the calculation, based on the values listed below:
+
+    method | Description
+    :-----:|------------------------------------------
+    0      | Returns 1 (Sunday) through 7 (Saturday).
+    1      | Returns 1 (Monday) through 7 (Sunday).
+    2      | Returns 0 (Monday) through 6 (Sunday).
+
+The method value defaults to 1.
+
+##### Return Value
+
+**integer** An integer value that reflects the day of the week.
+
+This is an integer ranging from 1 to 7, or 0 to 6, depending on the value of method.
+
+##### Examples
+
+```php
+$worksheet->setCellValue('A1', 'Date String')
+    ->setCellValue('A2', '31-Dec-2008')
+    ->setCellValue('A3', '14-Feb-2008');
+
+$worksheet->setCellValue('B2', '=WEEKDAY(A2)')
+    ->setCellValue('B3', '=WEEKDAY(A3,0)')
+    ->setCellValue('B4', '=WEEKDAY(A3,2)');
+
+$retVal = $worksheet->getCell('B2')->getCalculatedValue();
+// $retVal = 12
+
+$retVal = $worksheet->getCell('B3')->getCalculatedValue();
+// $retVal = 2
+
+$retVal = $worksheet->getCell('B4')->getCalculatedValue();
+// $retVal = 2
+```
+
+```php
+$retVal = call_user_func_array(
+    array('PHPExcel_Calculation_Functions', 'DAYOFWEEK'),
+    array('14-July-2008')
+);
+// $retVal = 7
+```
+
+##### Notes
+
+Note that the PHPExcel function is PHPExcel_Calculation_Functions::DAYOFWEEK() when the method is called statically.
+
+#### WEEKNUM
+
+Not yet documented.
+
+#### WORKDAY
+
+Not yet documented.
+
+#### YEAR
+
+The YEAR function returns the year of a date.
+
+##### Syntax
+
+```
+YEAR(datetime)
+```
+
+##### Parameters
+
+**datetime** Date.
+
+An Excel date value, PHP date timestamp, PHP date object, or a date represented as a string.
+
+##### Return Value
+
+**integer** An integer value that reflects the month of the year.
+
+This is an integer year value.
+
+##### Examples
+
+```php
+$worksheet->setCellValue('A1', 'Date String')
+    ->setCellValue('A2', '17-Jul-1982')
+    ->setCellValue('A3', '16-Apr-2009');
+
+$worksheet->setCellValue('B2', '=YEAR(A2)')
+    ->setCellValue('B3', '=YEAR(A3)');
+
+$retVal = $worksheet->getCell('B2')->getCalculatedValue();
+// $retVal = 1982
+
+$retVal = $worksheet->getCell('B3')->getCalculatedValue();
+// $retVal = 2009
+```
+
+```php
+$retVal = call_user_func_array(
+    array('PHPExcel_Calculation_Functions', 'YEAR'),
+    array('14-July-2001')
+);
+// $retVal = 2001
+```
+
+##### Notes
+
+There are no additional notes on this function
+
+### YEARFRAC
+
+Not yet documented.
+