hello, i want to use a COUNTA function to count the occupied cells in each
column in an excel spreadsheet. However, the cells i want to count are every
4th cell & not the ones inbetween. i can use =COUNTA(c7,c11,c15,c19....) but
my list size goes into to 1,000's & i only know how to enter the above
formula mannually. I need to know how to write the function/formula to count
every 4th cell automatically. i would be glad for anyone's help.

thank you!