“While the month-to-month movement has been uneven, more importantly we now have 15 consecutive months of year-over-year gains in contract activity,” said the Realtors’ chief economist, Lawrence Yun.

All regions saw gains in signed contracts for the West, where the bulk of the distress in the housing market has been. Foreclosures have been in high demand from investors, who are looking to cash in on the hot single family rental market.

That demand has pushed home prices higher in markets like Phoenix, Ariz., but it has also pushed supplies far lower. Yun said the West is now experiencing an, “acute inventory shortage.”

The association is projecting existing home sales to rise 8 to 9 percent in 2012 with another 7 to 8-percent gain in 2013. Analysts are split as to whether growing demand for housing will result in more home purchases or continued growth in the rental market. Credit remains tight, and many potential move-up buyers still owe more on their mortgages than their homes are currently worth.