• Population: 8.3 million
• New residents: 67,000
• Percentage gain: 0.8%

The largest city in the United States is also one of the most densely packed, with more than 27,000 people per square mile. Between July 2011 and July 2012, the Big Apple added 67,000 new residents, the biggest gain of any city in the country, according to the Census Bureau.

The government bailout of the banks has helped to bolster the city's ranks, according to Andrew Beveridge, a demographer at Queens College in New York. "The financial sector has not recovered completely, but it's doing pretty well," he said.

And with it, has come more jobs. New York's unemployment rate has been on a steady decline since its January 2010 recessionary peak of 10.5%. In April, it fell to 7.7%.

New York's improving jobs picture has made it especially attractive to immigrants from the economically troubled Eurozone, where unemployment has skyrocketed. "The Greeks and the Irish are showing back up," said Beveridge.

NEXT: Houston