Mapping with Mr. ZIP

ZIP code areas and what they can (and can't) do for you

I am often requested to map or facilitate the mapping of some data by ZIP code. The desired result is a thematic choropleth (or heat map) of sales/customer data for these ZIP code divisions . The request itself is not unreasonable, but filled with difficulties inherit to the nature and history of the US ZIP code system.

The problems mapping data by ZIP code areas ultimately originate with the idea that we live in a ZIP code. The very idea of a ZIP code area is ingrained in our minds as these static geographic units with definite boundaries that divide people into manageable groups-this concept even creeps in from pop-culture, ala Beverly Hills, 90210.