Have you ever heard of a calendar of "business months" (see details inside)?
I worked for a place that used what they called business months. I believe that it was used mainly for payroll purposes. The idea was that every business month would have an exact number of weeks. The only days that might be in a business month different from the calendar month were those days in weeks that contained days at the end of one month and days at the beginning of the following month. In those cases, the entire week would belong to whichever of the two months had a majority of days in the week. For example, this year September 30 falls on a Tuesday. The week containing September 30 contains the 3 days from September 28 to September 30 followed by the 4 days from October 1 to October 4. That would make the week the first week of the October business month.
I did a Google search for this and did not find anything, so I am guessing that this is not a common practice. Maybe just that one company worked with those types of calendars.
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