[Update 1: Corrects to nine cities reach new lows, adding city of Chicago.] Home prices in November dropped 1.6% from the year-ago period and are down 1% from a month earlier, according to the S&P/Case-Shiller composite 20-city home price index —a broad gauge of U.S. home prices. The 10-city composite was down 0.4%. Home prices were down in 16 of the 20 MSAs compared to a year ago, with just Los Angeles, San Diego, San Francisco and Washington, D.C., showing increases. On a month-to-month comparison in the 20-city composite, 19 of 20 had home price declines with only San Diego recording a scant 0.1% increase. Nine markets — Atlanta; Charlotte, N.C.; Chicago; Detroit; Las Vegas; Miami; Portland, Ore.; Seattle and Tampa, Fla., — hit their lowest points since home values peaked in 2006 and 2007, meaning that average home prices in those markets have fallen even further than the lows set in the spring of 2009. Since May 2010, home prices have slid. The 10-city composite has re-entered negative territory with a -0.4% annual growth rate in November, versus the +5.4% reported six months prior in May, and the 20-city composite was down 1.6% in November versus its +4.6% May print. “With these numbers more analysts will be calling for a double-dip in home prices. Let’s take a moment to define a double-dip as seeing the 10- and 20-city composites set new post-peak lows. The series are now only 4.8% and 3.3% above their April 2009 lows, suggesting that a double-dip could be confirmed before spring. “With an annual growth rate of +3.5% in November, Washington, D.C., was the strongest market, but still well below the +7.7% annual rate of growth seen in May 2010,” says David M. Blitzer, chairman of the index committee at Standard & Poor's. Fourteen MSAs and both composites have posted at least four consecutive months of decline with November’s report. U.S. house prices were unchanged on a seasonally adjusted basis from October to November, according to the Federal Housing Finance Agency's monthly house price index, also released on Tuesday. The table below (click to expand) summarizes the results for November 2010. The Case-Shiller indices have a base value of 100 in January 2000. So a current index value of 150 translates to a 50% appreciation rate since January 2000. Write to Kerry Curry. Follow her on Twitter @communicatorKLC.