The Fastest-Growing (and Fastest-Shrinking) Cities in America

Lower unemployment rates are associated with fast-growing populations.

Three Austin suburbs make the top 10 for fastest-growing cities.

Three Austin suburbs make the top 10 for fastest-growing cities.

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They say everything is bigger in Texas, and the state's cities seem to have taken it to heart. The Census Bureau on Thursday released estimates of the fastest-growing cities in America, and the Lone Star State claims 8 of the 15 cities that posted the fastest population growth from 2011 to 2012.

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San Marcos, a small city within the Austin metropolitan statistical area, posted nearly 5 percent population growth in just 12 months. The top 10 includes two other Austin suburbs, Cedar Park and Georgetown, plus Midland, a center of the oil industry, and Conroe, a suburb of Houston. The South and West are also well represented among the top 10, with Utah, California, Arizona, Georgia, and Tennessee also earning spots.

Below, the 10 fastest-growing cities in the U.S. last year:

City Percent Increase 2012 Population
San Marcos, Texas 4.91 50,001
South Jordan, Utah 4.87 55,934
Midland, Texas 4.87 119,385
Cedar Park, Texas 4.67 57,957
Clarksville, Tenn. 4.43 142,519
Alpharetta, Ga. 4.37 61,981
Georgetown, Texas 4.21 52,303
Irvine, Calif. 4.21 229,985
Buckeye, Ariz. 4.14 54,542
Conroe, Texas 4.01 61,533

Meanwhile, the 10 fastest-shrinking cities include several cities in the Rust Belt, but the Midwest, West, and even Texas are also represented:

City Percent Change, July 1, 2011 to July 1, 2012 2012 Population
Delano, Calif. -2.18 52,426
Montgomery, Ala. -1.21 205,293
Flint, Mich. -0.93 100,515
Yuma, Ariz. -0.78 95,429
Hammond, Ind. -0.69 79,686
Gary, Ind. -0.68 79,170
Detroit, Mich. -0.67 701,475
Port Arthur, Texas -0.61 54,010
Rockford, Ill. -0.59 150,843
Council Bluffs, Ill. -0.59 62,115

One factor that likely plays a part in these cities' population shifts is the local economy. The list of the fastest-growing cities also includes several cities with remarkably low unemployment rates — in March 2013, Midland had a jobless rate of 3.1, for example. Other places with similarly low unemployment rates include the Austin metro area (5.3 percent) and the Houston metro area (6.1).

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Likewise, several of the cities showing the greatest percentage decline in population have weak job markets. The Delano metro area posted a 13.6 percent jobless rate at last count, Detroit's jobless rate is pushing 10 percent, and Yuma, Ariz. is at an astounding 26 percent, which may be a function of its location on the Mexico border. High jobless rates are common in border towns, says Jim Diffley, chief regional economist at IHS Global Insight, as they often pull in many immigrants, many of whom may not have jobs, having just arrived in the country. Some have also pointed to the area's seasonal economy as a contributor to its high jobless rates.

High unemployment rates are likely a key factor pushing people out of those shrinking cities and into other places.

But job markets aren't the only determining factor. Population grows when people have babies or immigrate to the U.S., and Texas has both a high birth rate and high population of immigrants, both of which may help boost its cities toward the top of the list.

The census data also say something about where people want to live. While several of those fast-growing cities are suburbs, major cities in Texas aren't far behind, with Houston, Dallas, and San Antonio all growing at a nearly 2 percent rate. Indeed, the large number of small cities on the fast-growing list belie a broader trend of bustling urban centers, says one economist.

"Cities have become relatively more attractive than they had been over the last generation," says Diffley.

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Declining crime rates in many big cities, plus a generation of echo boomers who prefer big-city living and either can't afford or don't want to buy homes in the burbs, have helped to fuel a boom in big-city populations, says Diffley.

The Census data provide several examples of large cities whose growth rates are surpassing many of their surrounding areas. Charlotte, N.C., is growing at a 2.5 percent clip, far outpacing nearby Gastonia and Rock Hill. Likewise, Atlanta, Ga., is growing at 2.8 percent, beating suburb Sandy Spring and on par with nearby Roswell. Even Austin, Texas, with its multiple fast-growing suburbs, is growing at a quick 3.1 percent clip.

This fast growth in large cities is a relatively new phenomenon, says Diffley, but it could be short-lived. Millennials may be happy living downtown for now, but as they marry, have children, and seek out those multi-bedroom suburban houses, they may change their tune, moving fast growth back to the suburbs.

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