Articles

Essays and explainers on U.S. geographic data, ZIP codes, counties, and how to choose the right spatial unit for analysis.

• ZIP Codes Are Not Geography

  Why ZIP codes are a delivery artifact, not a spatial unit—and why this matters for analysis.

• Why County-Level Data Persists

  The historical, political, and practical reasons counties remain the backbone of U.S. data.

• Choosing the Right Geographic Unit: A Decision Framework

  A practical framework for deciding between ZIPs, counties, tracts, and more.