>>FUNCTION FourthFridayOfMonth(tnYear, tnMonth)
>>LOCAL lnDOW
>>lnDOW = DOW(DATE(tnYear, tnMonth, 01), 7)
>>RETURN DATE(tnYear, tnMonth, 7 - lnDow + 1 + 3*7)
>>
>>* or one-liner
>>FUNCTION FourthFridayOfMonth(tnYear, tnMonth)
>>RETURN DATE(tnYear, tnMonth, 7 - DOW(DATE(tnYear, tnMonth, 01), 7) + 1 + 3*7)
>>