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What’s the difference between a PMSA and an MSA?


Metropolitan Statistical Areas (MSA) are one or more counties that contain a city of 50,000 or more, whereas Primary Metropolitan Statistical Areas (PMSA) are subareas that meet the qualification to be an MSA, but have a population of one million or more. PMSAs are always part of a Consolidated Metropolitan Statistical Area (CMSA).

Here is a link to the metropolitan areas at the time of the 2000 Census:


The Detroit-Ann Arbor-Flint CMSA (2162) is comprised of the Ann Arbor PMSA (0440), the Detroit PMSA (2160) and the Flint PMSA ( 2640).

Dothan, Alabama (2180) is an example of an MSA.

Note that the metropolitan area definitions have changed since the 2000 Census. The new definitions (December 2009) are:


A good starting point is:


This link allows you to look at the definitions on selected dates for many different geographies. It will always include the latest standard.

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