First day of the week: distinguishing between displayed and calculated

A setting that distinguishes between display and calculation with the first day of the week. This is in line with how calendars display months in both computers and on physical calendars. But it is also useful for how calculates using the WORKDAYS() function, which currently uses the first of the week setting from admin. Many, including me, make an assumption that Monday is always the first day of the week for calculations. However, the setting of First day of the week is for both display AND calculations simultaneously. I don’t remember the last time a date picker started its week display on Mondays, possibly never (I live in North America). Certainly, our physical, printed calendars always display Sunday as the start each week. I would not want users to annoyingly have to readjust how they look at calendars every time we have to look at a calendar with Mondays being the start of the week.

The difference between display and calculated start of week should be made explicit in the settings. I recommend two distinct settings for this:

  • First day of the work week for calculations
  • Last day of the work week for calculations
  • First day of the week for calendar displays

I also agree with a related post that this should be made a user-overridable setting from what is in the admin setting.