Perpetual Date List for Data Validation

To create a list of twelve dates that do not have to be updated manually begin by entering the name of the list in Cell A1. For this example "validDates" has been used but any unique name will work. In cell A13 enter this formula - =TODAY(). In Cell A12 enter this formula = EDATE(A13,-1). Copy Cell A12 and Paste in Cells A2 thru A11.

Typically these dates will be used for as Month/Year (Billing Period, etc) so the day is not important. The cells containing the dates can now be formatted as desired (i.e. Apr-2011, April, 2011).

Now assign the list a name and it's ready to use for Validation. The quickest way to give the range a name is to select cells A2 thru A13 and then click in the "Name Box" (the box to the left of the Formula Bar that normally displays the address of the active cell) and type validDates or whatever name you prefer. Press enter and the entry is assigned to the range of cells.

The list of dates can now be used in for Data Validation by the assigned name.