Returns the number of days in a month : MONTH « Date Time functions « Microsoft Office Excel 2007 Tutorial

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15.8.3.Returns the number of days in a month

Input the formula: =DAY(DATE(YEAR(A1),MONTH(A1)+1,0))

15.8.MONTH
	15.8.1.	MONTH(serial_number) converts a serial number to a month
	15.8.2.	Determining the Last Day of a Month
	15.8.3.	Returns the number of days in a month
	15.8.4.	Determining Whether a Year Is a Leap Year
	15.8.5.	Returns an integer between 1 and 4 that corresponds to the calendar quarter for the date

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