Home price indexes from CoreLogic and Lender Processing Services (LPS) both recorded continuing declines through the month of October.

CoreLogic’s study shows national home prices dropped 1.3 percent between September and October, marking the third straight monthly decline.

The company puts October home prices 3.9 percent below their year-ago levels. That follows a decline of 3.8 percent in September 2011 compared to September 2010.

“Home prices continue to decline in response to the weak demand for housing,” commented Mark Fleming,

CoreLogic’s chief economist. “While many housing statistics are basically moving sideways, prices continue to correct for a supply and demand imbalance.”

Fleming says looking forward, CoreLogic’s forecasts indicate flat growth through 2013 for residential home prices.

LPS says its preliminary data indicates the same downward trajectory for home prices, with a 1.1 percent month-over-month decline for October, coming on the heels of a 1.2 percent drop in September.

Kyle Lundstedt, managing director for LPS Applied Analytics, says the latest data is consistent with seasonal patterns occurring since 2009.

“Each year, prices have risen in the spring, but revert in autumn to a downward trend that has not only erased the gains, but has led to an average 3.7 percent annual drop in prices to date,” Lundstedt explained.

LPS’ latest index of average national home prices continues the downward trend begun after the market peak in June 2006, when the company says the total value of U.S. housing inventory stood at $10.6 trillion.

The value has declined 30.2 percent since that peak to $7.56 trillion.