The Standard & Poor's/Case-Shiller U.S. National Home Price Index tumbled a record 15.4 percent during the quarter from the same period a year ago.

The monthly indices also clocked in record declines. The 20-city index fell by 15.9 percent in June compared with a year ago, the largest drop since its inception in 2000. The 10-city index plunged 17 percent, its biggest decline in its 21-year history.

No city in the Case-Shiller 20-city index saw year-over-year price gains in June, the third straight month that's happened.

However, the rate of single-family home price declines slowed from May to June, a possible silver lining, the index creators said.

"While there is no national turnaround in residential real estate prices, it is possible that we are seeing some regions struggling to come back, which has resulted in some moderation in price declines at the national level" said David M. Blitzer, chairman of the index committee at S&P.