NEW YORK - May 31, 2011 - Home prices began double dipping months ago, but now that S&P/Case Shiller has chimed in, it really must be so.

The S&P/Case Shiller composite index of 20 metropolitan areas declined 0.2% in March from February on a seasonally adjusted basis, in line with economists' expectations.

This report is the most widely followed home price index, equally quoted in bank boardrooms, Treasury Department back rooms, and Congressional Committees.

The report finds home prices in Q1 of this year are now 2.9% below the previous quarterly bottom in Q1 of 2009, effectively giving up all the gains of the past few years, which were of course fueled by the home buyer tax credit.

"Just about everybody agrees we're going to miss the seasonally strong period in 2011, which we should be at the very beginning of right now with May, but nobody thinks that will make any difference," says S&P's David Blitzer. "Everybody's now keeping their fingers crossed for 2012 and wondering whether people just don't want to own homes anymore."