problem i have 300.000 entries
Colum A = YEAR Colum B = month Colum C = customer number G5 to G13 = criteria
I want to count how many unique customers pr. year - I tried using an array formula - but that is no good on such a huge data set... i guess...
or in english:
This works fine just fine if i have a small data set - but with my dataset it just starts to calculate and then stay at 100% cpu for hours
So what do I do ?