%mlink(STRY:; PHOTO:; AUDIO:%)

WASHINGTON (AP) _ Federal Reserve Chairman Alan Greenspan said Friday that policy-makers are being challenged by dramatic gains and losses in the stock market and less volatile movements in home prices.

The challenge, he said, is for policy-makers to try to better understand how gains or losses on stock investments and in home values affect consumers' willingness to spend.

Consumer spending accounts for two-thirds of all economic activity and has been a main force propping up the struggling economy. The yearlong economic slowdown has led to a slide in the stock market. But the value of homes, for the most part, have gone up.

``There can be little doubt that sizable swings in the market values of business and household assets have created important challenges for policy-makers,'' Greenspan said in a speech delivered at the Fed's annual retreat in Wyoming's Grand Tetons. The text was distributed in Washington.