I have an Excel file with data on 200 customers. The only geographic data I have is 5 digit ZIP code. All customers are within a similar geographic region (i.e. not spread out nationwide.)

How do I create a map with graduated shading to indicate those zip codes with more customers?

I need a field to indicate a count of customers per zip code I suppose and I tried this with a pivot table in excel.

I get a table with about 50 zipcodes and the count of customers for each. The problem is when I try to map this data in MapPoint, I am told I have "more than 8 unique data items" and can't map them.

Obviously I am missing something very fundamental.

Thanks for any replies.