Hello JP,
If you do not want to use a Pivot Table select a sufficiently long
range with two columns and array-enter
=Pstat("count",TEXT(C1:C999,"YYYYMM")="200912",B1: B999,A1:A999)
Pstat you can find he
http://sulprobil.com/html/pstat.html
Regards,
Bernd