Thanks for checking.

>Perfect! Works up to Nov.9998 :)
>
>>Hi Sergey,
>>
>>Is this better? :)
>>

>>ldLastOfYear    = DATE(lnYear, 12, 31)
>>lnWeeksInYear   = MAX(WEEK(ldLastOfYear,1,2), WEEK(ldLastOfYear-7,1,2))
>>lnWeeksPerMonth = MOD(WEEK(GOMONTH(ldFirstOfMonth,1),1,2) + lnWeeksInYear - ;
>>					WEEK(ldFirstOfMonth,1,2), lnWeeksInYear)
>>

>>Counting sundays could be simpler in this case though.
>>
>>>Sorry for delay, I've been on vacation:)
>>>I've tested your code against mine. It gives wrong results for Decembers in some years, e.g. in 2000, 2006, 2012, 2017, 2023, ...
>>>
>><snip>