Specifying Different Weekends with NETWORKDAYS

Sunil can use the NETWORKDAYS function to return the number of regular business days between two dates. The function assumes that Saturday and Sunday are not work days, but in Sunil's organization only Sunday counts as a non-work day. He wonders if there is a way to use NETWORKDAYS and specify that only Sunday should be excluded from the count returned.

You can determine this by using a formula based on the NETWORKDAYS function. Assuming that the starting date is in A1 and the ending date is in B1, the following formula examines the days between the two dates and essentially return a count of non-Sunday days in that range:

=NETWORKDAYS(A1,B1)+SUMPRODUCT(--(WEEKDAY
(ROW(INDIRECT(A1&":"&B1)))=7))

Of course, since Sundays are the only day of the week being excluded, you could simply skip the use of NETWORKDAYS and use SUMPRODUCT to figure out if the day should be counted or not:

=SUMPRODUCT(--(WEEKDAY(ROW(INDIRECT(A1&":"&B1)))>1))

If you expect that there may be holidays in the range, and that those holidays are in the named range "holidays," then you'll need to go back to using NETWORKDAYS in the formula:

=NETWORKDAYS(A1,B1,holidays)+SUMPRODUCT(--
(WEEKDAY(ROW(INDIRECT(A1&":"&B1)))=7),--
(NOT(ISNUMBER(MATCH(ROW(INDIRECT(A1&":"&B1))
,holidays,0)))))

Other variations of what constitutes the work days in a week have been covered by Chip Pearson at his site:

http://www.cpearson.com/excel/betternetworkdays.aspx