The Cost of Living Adjustment (COLA) data we use is based on a cost of living index from the Council for Community and Economic Research. The index uses average costs of over 60 goods and services collected at the local (ZIP-code) level from over 300 independent researchers and is the only local level cost of living index currently available for the US. Our Median Household Income (MHI) index uses the most recent data available from the US Census Bureau.