Just the Facts

Sources & Methodology

Every figure in the explorer traces to a primary source — and the computed and inflation-adjusted figures are derived in the open.

Data sources

Inflation adjustment

When “Adjust for inflation (2025 $)” is on, every dollar metric is shown in constant 2025 dollars so amounts from different years can be compared on equal footing. Each year’s nominal value is scaled by the ratio of the 2025 price index to that year’s index:

constant 2025 $ = nominal $ × ( CPI2025 ÷ CPIyear )

The index is the U.S. Bureau of Labor Statistics CPI-U (Consumer Price Index for All Urban Consumers, U.S. city average, all items), annual average, series CUUR0000SA0 (1982–84 = 100), covering 1994–2025. The base year is the latest published annual average (2025). For example, $1.00 in 1994 is about $2.17 in 2025 dollars.

This is a display-time transform only — stored observations remain verbatim and nominal (see below). A figure for a future period with no published CPI yet (e.g. a proposed budget) is left nominal rather than estimated. Source: U.S. Bureau of Labor Statistics — CPI-U (annual average).

Computed figures

Observations are stored exactly as reported by their source. Ratios and normalizations are computed at query time, never stored: General Fund surplus (revenue − expenditure), full-value tax rate (levy ÷ taxable full value × 1,000), per-pupil figures (÷ K-12 enrollment), and per-capita figures (÷ Census population). Each computed series inherits its inputs’ citations and the more cautious of their certainty levels.

Raw dollar totals scale with size, so compare municipalities per-capita and school districts per-pupil. Metrics measured on different bases — nominal vs. full-value tax rates, or different staff-FTE definitions — are flagged and never plotted as one series. Cross-entity-type comparisons (e.g. a town vs. a school district) are allowed but caveated, not blocked.