Census Bureau report out

The Census Bureau has released its Report on Income, Poverty and Health Insurance Coverage in the United States: 2008. Lots of web comments about the inflation adjusted median income falling below the 1998 median. I see another startling fact. On page 4 the report notes that "[a]pproximately 31.0 percent of the population had at least one spell of poverty lasting 2 or more months during the 4 year period from 2004 to 2007."