The housing market data just gets worse. According to a housing index released by Standard & Poor's, prices of single-family homes across the nation depreciated in January compared to a year ago. Furthermore, the decline was the worst in more than 13 years.

The S&P/Case-Shiller composite index showed a drop of 0.7 percent from a year ago in the price of a single-family home based on existing homes tracked over time in 10 metropolitan markets.