Use the Time ID Creation from Starting Date window to add a SAS date valued time ID variable to an input data set. This is a convenient way to add a time ID of any interval as long as you know the starting date of the series. To access this window, select "Create from starting date and frequency" from the Create pop-up list in any window where you can select a Time ID variable. For more information, see ChapterĀ 55: Creating Time ID Variables.