It’s not only Phoenix where home prices are falling.

U.S. home prices fell 1.4 percent in the first quarter compared to a year ago, the first time since 1991 prices have shown a quarterly decline, according to a housing index released Tuesday by Standard & Poor’s.

Boston, Detroit, San Diego and Washington, D.C. showed the greatest year-over-year declines in prices. Meanwhile, Charlotte, N.C., Seattle and Portland, Ore. had strong price appreciation over last year. Compared to February, the gains in those cities were more modest.

This has got to be a concern for the Federal Reserve, however, the rest of the economy is so strong that they are reluctant to lower rates and possibly spur inflation.

Detroit and San Diego posted the biggest annual declines of 8.4 percent and 6.0 percent, respectively.

Phoenix and Las Vegas have seen the largest price slides from their peaks. In September 2005, Phoenix showed a 49.3 percent growth rate and Las Vegas jumped 53.2 percent in September 2004. Those cities in March had respective price drops of 3 percent and 1.6 percent.