Standard & Poor’s Ratings Services lowered its corporate credit and senior note ratings on KB Home late Monday, sending shares down 4 percent early Tuesday.

The rating agency said it lowered the credit rating for the Los Angeles homebuilder to ‘BB’ from ‘BB+’, reflecting the company’s weak first quarter results and very difficult housing market.

Standard & Poor’s also said the outlook remains negative as a slow housing market as well as constricted lending practices will continue to take a toll on KB Home and its peers.

“Given the current conditions, KB Home’s earnings and profitability, as well as its already weak credit metrics, will likely continue to be pressured,” the agency said in a statement.

Shares in KB Home dropped 4 percent to $23.51 in early trading Tuesday.