Kavanagh says 2,856 chain retail stores closed in the first half of 2009, compared with 3,272 closings in the same period of 2008. The vacancy rate at shopping centers climbed from 6.7 percent in the fourth quarter of 2008 to 7.6 percent in the third quarter of 2009. At the same time, average rents have declined 3.8 percent over the past year.

Complicating matters, much of the downturn in commercial real estate is located in areas that have also suffered from residential real estate problems caused by foreclosures and job losses. Among the worst markets are California, Nevada, Florida, and Arizona.

Foresight maintains a “watch list” of banks that it says are at an elevated risk of being closed in the next three to four quarters. The latest list includes banks in Florida and California in the top 10, but also lists lenders in Georgia, Minnesota, and Washington State in the top six. In those three states, construction lending was the major problem.

The signs of commercial real-estate-related stress appeared in earnest during late 2009. In October, Capmark Financial group, one of the largest commercial real estate lenders in the nation, filed for bankruptcy protection after recording a $1.6 billion quarterly loss. The Horsham, Pennsylvania-based Capmark had $10 billion in commercial loan originations.

And three small lenders in Florida, Hillcrest Bank and Partners Bank in Naples, and Flagship National Bank in Bradenton, were taken over by the FDIC. While their commercial loan books were much smaller than Capmark’s, ranging from $13 million to $38 million, the three Florida lenders had default rates from 7.6 percent at Flagship to 45 percent in the case of Hillcrest, according to SNL Financial, a research firm in Charlottesville, Virginia.

“Working out these loans is going to be a slow and painful process for the next two to three years,” Kontokosta says. He says there is a tendency on the part of both lenders and owners to extend the loans as long as possible, putting off refinancing as long as they can.