So far, governments have portrayed any such suggestions as foreign efforts to exploit local weakness.

ECONOMIST: The challenge from up north | The

For some of the cities on our list, the big problem is the weakness of their local economies.

FORBES: Cities Where Home Prices Are Still Tumbling

Greg Heym, an economist at Brown Harris Stevens and Halstead, said the slowdown likely reflected weakness in the local job market, including last year's loss of 4, 300 jobs in the securities industry between April and December.

WSJ: Property Slips in Manhattan