RICHMOND, Va. -- Auto retailer CarMax said Thursday its fourth-quarter profit jumped 72 percent as lower expenses and a profit in its financing arm offset the impact of falling sales, according to The Associated Press.

The earnings beat Wall Street expectations but revenue fell short. Its shares climbed almost 10 percent in premarket trading.

CarMax said it couldn't offer a financial forecast for this fiscal year, citing unprecedented declines in traffic and sales and volatility in the credit market.

But it cautioned that if trends do not improve, it anticipates a double-digit decline this year in used car sales at stores open at least a year.