The 10-City Composite gained 4.6% year-over-year, while the 20-City Composite gained 4.9% year-over-year. The S&P/Case-Shiller U.S. National Home Price Index, covering all nine U.S. census divisions, recorded a 4.2% annual gain in April 2015 versus a 4.3% increase in March 2015.

After seasonal adjustment, the National index was unchanged; the 10- and 20-city composites were up 0.3% and 0.4%.

For the first time since all the way back in September, minus signs suddenly appear on the city breakdown list with 8 of 20 cities showing contraction in April. Cleveland shows the sharpest monthly contraction at minus 0.5 percent followed by Atlanta and Chicago at minus 0.4 percent each.

But several on the plus side show significant strength led by Minneapolis at a monthly plus 1.0 percent followed by Denver, Detroit and Las Vegas at plus 0.9 percent. Year-on-year, Denver and San Francisco lead the list at plus 10.3 and 10.0 percent with Dallas in third at plus 8.8 percent. Those showing the least year-on-year growth are Washington DC at plus 1.1 percent, Cleveland at plus 1.3 percent, and Boston at plus 1.8 percent.