PetsMart's ( PETM) fourth-quarter earnings more than doubled on strong sales at its older stores.The pet supply retailer earned $57.24 million, or 39 cents a share, in the quarter, compared with $24.55 million, or 17 cents a share, in the fourth quarter of 2002. The year-ago results were weighed down by a charge related to a legal settlement of $13 million, or 9 cents per share. Sales at PetsMart increased 13.4% in the fourth quarter from the same period a year earlier to $839.74 million. On a same-store basis, which compares results of stores open more than one year, sales jumped 7.7%. While the company's earnings surpassed estimates, its sales fell a bit short. Analysts polled by Reuters' MultexNet service were expecting PetsMart to earn 36 cents a share on $847.87 million in sales. The pet supplies chain forecast earnings of 21 cents a share in the first quarter and a range of $1.14 to $1.15 for its fiscal year. The company expects same-store sales to increase 7% both in the first quarter and for the full year. Both earnings estimates were slightly above Wall Street's consensus. Analysts had predicted profits of 20 cents a share in the first quarter on sales of $790.83. For 2004, Wall Street was looking for $1.13 in earnings on $3.43 billion in sales. In recent trading, PetsMart's stock was up a penny to $26.66.