Bruce Katz, Mark Muro, and Jennifer Bradley of Brookings highlight the economic impact of metro areas:

California, it is often noted, accounts for more than a tenth of the national economy. That’s truebut somewhat misleading. The “California economy” is not evenly spread across the state, but rather it is driven by a few metropolitan areas. The Los Angeles and San Francisco metropolitan areas are responsible for more than half the state’s economic clout. Along with San Diego and San Jose, they together contribute 72 percent of the state’s GDP. True, if California were its own country it would have the eighth largest GDP in the world, but if these four metros alone were a separate nation, they would outpace India, Mexico, South Korea, and Australia.

Ryan Avent adds his own two cents.

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