I’ve got a table with dates, and would like to fill in a 12(months, B1:M1) x 31(days, A2:A32) with the number of days for each month/day combination. The column with dates is named (“C_ddays”), so I started by using the “wizard” which resulted in putting “=countif(day(C_dday),=A2)” and that returned “Err:510”.

Next try was “=countif(day(C_dday),”=A2")" (Err:504)

Next try was “”=countif(day(C_dday),"="&A2)" (Err:504)

So what is the way to do it???

Turns out that it works using “sumproduct”. Not very intuitive.