CHARLOTTE, N.C. — If you are looking for a sign the economy is still in need of repair, you can find it at Lowe's Cos.

A struggling economy and continued turmoil in the housing market drove the nation's second-biggest home improvement retailer to report a nearly 18 percent drop in first-quarter earnings from a year earlier and lower its guidance for the year on Monday.

"It's been a challenging sales environment," said Lowe's Chairman and Chief Executive Robert A. Niblock. "As we continue on in a tough environment, with rising other costs for the consumer, be it food or fuel or whatever, what happens on the employment front has yet to be seen and can certainly be more tough on more consumers."

Mooresville, N.C.-based Lowe's said net profit in the period ended May 2 fell 17.9 percent to $607 million, or 41 cents per share, from a year earlier. Sales slipped to $12.0 billion from $12.2 billion a year ago.