I have to tally a year's worth of monthly data of attendees by one county's
zip codes into one main list of zip codes. (ie. San Francisco County has 20
zip codes, in January only 8 zipcodes were represented, February 10 were
represented, etc.) How do I tally each month's zip codes and attendee count
into the main excel sheet w/ all of SF's zipcodes if the not all zip codes
fields are used each month?

Are you asking for advice on how to lay the data out, or how to
achieve the tally?

I would suggest if you have a list of all the zip codes in column A
starting with A2, then you can put 1, 2, 3 etc in B1, C1, D1 etc to
represent months. Then you can use a SUMPRODUCT formula to give you
the totals against each zip code for each month.

As you do not give any details of how your data is laid out, I can't
give you a suggested formula, so post back with more details if you
need further advice.

Hope this helps.

Pete

On Sep 18, 5:48*pm, jayh wrote:
I have to tally a year's worth of monthly data of attendees by one county's
zip codes into one main list of zip codes. *(ie. San Francisco County has 20
zip codes, in January only 8 zipcodes were represented, February 10 were
represented, etc.) How do I tally each month's zip codes and attendee count
into the main excel sheet w/ all of SF's zipcodes if the not all zip codes
fields are used each month?