ATLANTA — The Home Depot Inc. doesn't know if stimulus checks making their way to potential customers are enough to improve its fortunes this year, the company said Tuesday as it reported a 66 percent drop in first-quarter profit.

The world's largest home-improvement store chain did not give detailed guidance for the remainder of fiscal 2008, saying only that it was "more comfortable" with the low end of its previous expectations.

Its shares fell $1.50, or 5.2 percent, to $27.37.

The challenge for Home Depot, like its smaller rival Lowe's Cos., is a slumping U.S. housing market. Seventy percent of Home Depot sales come from homeowners, while the other 30 percent come from professionals such as contractors, according to the company. Eighty-nine percent of its stores are in the United States, where home foreclosures are accelerating around the country.

The Atlanta-based company said it earned $356 million, or 21 cents a share, in the three months ending May 4, compared with a profit of $1.05 billion, or 53 cents a share, a year earlier.