Although week numbers are never used in worldwide public holidays, it is possible to construct a recurring holiday rule that is based on week numbers, and this is sometimes used to specify the date of an insertion.

 

The fixed date recurrence rule for the weekday of a given week number is:

 

((7*(w-1))+(D-1)-3) days after the Thursday on or after January 1

 

where W is the week number and D is the weekday (running from 1-7 for Monday to Sunday).

 

For your convenience, the value of ((7*(w-1))+(D-1)-3) (the offset) has been calculated for the Monday (D=1) of all week numbers from 1 to 52.

 

 

* note that if the offset value is negative, then the rule above should change from "days after" to "days before".

 

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Topic 186610, last updated on 24-Apr-2022