This comment has been tabled by several delegations such as GR-113, CO-203, CL-173, GB-436, US-232:
Part 4, Section 3.17.7.344 WORKDAY
Problem: This function is defined to skip over weekends in its calculations, but weekend is not defined and has different definitions in different parts of the world.
Solution: Define this function unambiguously and preferably in a way which provides for cultural adaptability in the definition of a weekend.
The DIS29500 website has an indication on how ECMA/Microsoft is ignoring the Muslim world, as they refuse to correct the WORKDAY function for the Muslim world:
We agree that the implementation of WORKDAY makes assumptions as to which days of the week are weekdays versus weekends. In order to maintain backwards compatibility with the corpus of existing documents, no semantic change will be made to the function. A spreadsheet application could create a new function which would allow for specification of which days of the week are workdays.
The following change will be made to Part 4, §3.17.7.344, page 2,821, line 21.
3.17.7.344 WORKDAY
Description: Computes the serial value of the date that is day-offset working days offset from start-date. Weekend days (Saturday and Sunday) and any holidays specified by holidays are not considered as working days.
Microsoft/ECMA rolls over cultural diversity. Does someone wants to call Al Jazeera?