This seems to be a very easy problem, but I can't for figure it out.
I have a file of 92,000 customer records. Each record has a zip code. At the most I have 90 different zip codes on the file. I want to map these 92000 records by their zip code, and then color code the zip codes by the count of customers in each zip code, so I can see which zip codes have the highest counts, on down. How do I make ranges that state my count levels:
0-500 is red
501-1000 is blue