LOS ANGELES -- Average home prices in the nation's 20 biggest cities rose 2.2 percent in May from the prior month, according to the Standard & Poor's/Case-Shiller index.
The gain was the second after seven months of declines and was the strongest month-over-month percentage rise in more than a decade. The key index was still down 0.7 percent compared with May, 2011.
All 20 cities in the index posted positive monthly results.
Chicago, Atlanta, and San Francisco posted the biggest monthly increases.
Detroit, San Diego, and Charlotte posted the smallest gains.