Kbase Article of the Week: ClarisWorks: Week of Year Based on Fiscal Year »

Apple Support:

Let’s say you would like to know what week of the year a certain date falls on. FileMaker Pro and ClarisWorks both have a WeekofYear function which returns the number of weeks from January 1 based on a supplied date. If you want to calculate the number of weeks starting at a date other than January 1, as in a fiscal year beginning date, you can use the following calculation given your file contains the field ProjectDate:

Week of Year (calculation, number result) = INT ((ProjectDate – Date (3,1,Year (ProjectDate)))/7)+1

The Date function is where the start date is formed. In this example, the start date is 3/1 of the year of the ProjectDate.