Data sources

ZIP codes and locations

Distances and locations are worked out from US postal code data by GeoNames, used under the Creative Commons Attribution 4.0 license. We removed military APO and FPO codes, which have no fixed location in the United States. Each ZIP code stands for a point near its center, not an exact address.

Makes and models

Model names and list prices come from manufacturers' and distributors' own websites, and model years from press coverage and reference sources. Prices change, so treat a list price as a guide and confirm it with a dealer.