When will it end? Housing just keeps on sliding into a black hole. The December numbers top off a truly terrible year:

WASHINGTON (MarketWatch) -- Capping the worst year for the housing market in 25 years, resales of U.S. homes and condos fell 2.2% in December to a seasonally adjusted annual rate of 4.89 million, the National Association of Realtors reported Thursday.

For all of 2007, sales of single-family homes fell 13%, the biggest decline since 1982. The median sales price of an existing single-family home fell for the first time in the 40-year history of the survey, dropping 1.8%. Although no hard data are available, most economists believe median home prices hadn't fallen since the Great Depression of the 1930s. December resales at 4.89 million were weaker than the 4.98 million pace expected by economists surveyed by MarketWatch.