The number of home sales contracts signed in August fell 2.6% from July as the nation continued to struggle back from one of the deepest housing downturns since the Great Depression, according to National Association of Realtors data.

NAR found the real estate recovery is still underway, although it remains subject to many headwinds and market volatility. The NAR data reflects real estate contracts and not closings.

From last year, August pending home sales grew 10.7%, suggesting overall improvement in 2012.

The association's pending home sales index also fell to 99.2 in August, down from 101.9 in July, but up from 89.6 last year.

"The performance in month-to-month contract signings has been uneven with ongoing shortages of lower priced inventory in much of the country, and across most price ranges in the West, but activity has remained at notably higher levels this year," said Lawrence Yun, chief economist for NAR.  

To date, the pending sales index has managed to climb for 16 consecutive months in a row year-over-year. Home sales were relatively flat from 2008 through 2011, Yun said. But in 2012, annual gains have become more routine.

Yun believes existing home sales will rise to 9% or 4.64 million units in 2012 and forecasts another 8% gain next year.