Returns the number of days in a month.
This function is only available if the Analysis AddIn is installed.
- returns the number of days in the month in which date lies.
- returns 29, the number of days in February 2012 (2012 is a leap year).
DAYSINMONTH is not part of the forthcoming ODFF international standard, and should not be regarded as portable. An alternative would be DAY(DATE(YEAR(date);MONTH(date)+1;0)).