Index methodology

What the number is, and is not

The published value is a composite index. A result of 113 means the weighted measures in this registry sit 13% above the national value of the same measures. It does not mean a household spends 13% more.

• It is not a statement that a typical household here spends this much more or less than a typical United States household.
• It is not a household budget, a market basket, or a spending forecast.
• It is an index of the measures listed below, weighted by category, relative to the national value of those same measures.

Known limits of the composite

These are properties of the method, not data gaps. They apply to every location.

• Within a category, every available measure carries equal influence. Housing, for example, averages home value, rent, owner costs, and burden measures as if a household were equally exposed to each.
• Energy averages electricity and natural gas equally, although natural gas use varies sharply by climate, heating system, and whether a home is connected to gas at all.
• A category represented by a single loaded measure gives that measure the category's entire weight. Transportation currently rests on commute time alone.
• Statutory facts that reduce cost, such as a state with no individual income tax, appear as a measure at or near zero rather than as a separate offsetting credit.
• Food, health care, insurance, goods, and child care have no weighted measure, so they cannot move the index in either direction.
• Contributing measures come from different reporting periods: ACS 5-year estimates, EIA energy releases, and state tax-year records are combined into one number.
• Tax measures built on externally sourced local averages are held at pending verification and excluded from the index until the publisher is confirmed.

Indexing a single measure

Every measure is converted to an index where 100 equals the benchmark, which is the national value. A cost measure indexes as value divided by benchmark. A measure where a higher number means lower pressure on a household budget, such as median household income, is inverted so that a higher index always means costlier. Missing values are never treated as zero; they are excluded and reported as not available.

Category weights

A category index is the mean of its available measure indexes. The overall index is the weighted mean of the available categories. When a category has no data for a location, its weight is removed and the remaining weights are renormalized, and the resulting coverage ratio is shown on the scorecard.

Context-only categories carry no weight until a verified national dataset is loaded for them: Goods and Services, Homeowners Insurance, Health Care.

The five-level scale

Index values are grouped into five levels. Each level has a color and a text marker, so the scale is readable without relying on color.

• − −Much lower costIndex below 92
• −Lower costIndex 92 to 97.5
• =Near benchmarkIndex 97.5 to 102.5
• +Higher costIndex 102.5 to 110
• + +Much higher costIndex above 110

Geographic resolution

Census measures are reported for states and counties. Energy prices are reported by state, so a county view reuses its statewide value and labels it as statewide. Nothing is interpolated between geographies, and no value is invented where an agency reports none.

Limitations

• Survey estimates carry sampling error, which is larger for small counties.
• Reporting periods differ between sources, so a comparison can mix a 2023 survey estimate with a 2025 energy price.
• The electricity estimator covers supply cost only and excludes delivery charges, fixed fees, taxes, and utility-specific rate structures.
• The score is a planning aid, not a household budget and not financial advice.