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Method

How the county GDP and income figures are made

How the pages of the Economy hub read what their publishers put out, and what that record can and cannot say. The method every topic shares — where a figure comes from, snapshots, freshness and corrections — is on the site’s methodology page.

What the figures are

The Bureau of Economic Analysis publishes county accounts once a year: each county’s gross domestic product and its personal income, with its population and its personal income per resident. The pages read three of BEA’s county tables through its Regional API, and BEA is the cite beside every figure. Each release revises earlier years as well as adding one, so a figure here may differ from one BEA published before.

This product uses the Bureau of Economic Analysis (BEA) Data API but is not endorsed or certified by BEA.

Which dollars

Real GDP is in chained 2017 dollars, which remove price change between years. Personal income is in current dollars, which do not, so a comparison of two years of personal income is not adjusted for inflation. A page names the dollars beside every dollar figure. BEA publishes its tables in thousands of dollars, and the queries turn each into whole dollars before a page prints it.

Estimates, and two different measures

A county’s GDP is BEA’s estimate, not a count of output that businesses reported, and its personal income is BEA’s estimate of the income of the people who live there. GDP and personal income measure different things, and no page presents one as a check on the other.

How the rankings are made

Each ranking orders the counties that have a published figure, highest first, for the newest year the tables hold. A tie gives every tied county the same rank, and the next rank is skipped. Every county is ranked in its own state’s list as well as in the national one, and a national page prints the top of its ranking and links each state list.

Change on the year before

The two change rankings are computed by the queries from BEA’s levels for the newest year and the year before: the newest level over the earlier one, less one, as a percent. They are not BEA’s own published percent changes, and they can differ from them. A county with a small level moves by a large percent for a small change in dollars, so each page prints both levels beside the change.

Figures BEA does not publish

BEA withholds some county figures, and marks them in place of a value. A withheld figure is never counted as zero, never estimated and never ranked. Every ranking says how many counties it leaves out for that reason, nationally and in each state. A county that has a figure for the newest year and none for the year before is left out of the change rankings and counted.

Connecticut

From 2024 BEA’s estimates for Connecticut are for its planning regions and not its counties. The newest year therefore has no figure for Connecticut’s counties and a figure for each planning region, which is not a county and is not ranked with the counties. The Connecticut page prints the planning regions’ figures beside the counties BEA lists for the state, unranked, and every national count says that Connecticut is set aside.

Names of places

A county is named as BEA names it, with the state’s abbreviation, and the asterisk BEA appends to names it footnotes is left off. A name with a plus sign is one area that BEA publishes under one code, such as a Virginia independent city combined with the county beside it; the pages do not split it or combine it with another. A state is named in its full form, and the District of Columbia as the District of Columbia.

Metropolitan areas

BEA discontinued its metropolitan and micropolitan area series for GDP and personal income with the 2024 county release and continues to publish by county. The hub has no metropolitan page, and no page here prints a metropolitan figure.

Where the pages are listed

The hub is not listed yet. Its pages are reachable by their URLs, are not in the search index and are not in the sitemap, until the hub is read on its contact sheet. Counties have no page of their own yet, so a county appears in a ranking and on its state’s page.

What the figures cannot show

The tables record how large a county’s output and income were in a year and how they changed. They do not say why a county’s economy is large, small, growing or shrinking, what industries produce its output, or how its residents fare, and no page says that they do. A large GDP is not a measure of how well a county is doing, and a ranking is not a verdict.

What this data cannot show

  • Real GDP is in chained 2017 dollars and personal income is in current dollars, which are not adjusted for inflation. A county’s figure is BEA’s estimate, and BEA revises earlier years with each release.
  • A figure BEA withholds is not ranked and is counted beside the ranking. From 2024 BEA’s Connecticut estimates are for its planning regions and not its counties, so Connecticut is not ranked with the counties.
  • GDP and personal income measure output and income. These figures do not say why a county’s economy is large or small, or why it changed.

Sources

Data retrieved