COVINGTON, La., April 18, 2013 (GLOBE NEWSWIRE) -- Pool Corporation (Nasdaq:POOL) today reported results for the first quarter of 2013. "As anticipated, 2013 started with a more normalized onset to the season versus 2012, which impacted both sales and margins. We realized sales growth despite one less selling day and the tough comparison, given last year's unusually mild winter. We were also able to maintain good pricing discipline and expense management," said Manuel Perez de la Mesa, President and CEO. Net sales for the quarter ended March 31, 2013 increased 2% to $370.4 million, compared to $362.0 million in the first quarter of 2012. Sales in the first quarter of last year benefited from record warm temperatures across the Northeast and Midwest, which prompted an earlier than normal start to the 2012 season. This shift contributed to sales growth of 16% in the first quarter of 2012 over the first quarter of 2011. Base business sales were up 2% in the first three months of 2013. The impact of weather on our first quarter results is evidenced by growth of approximately 10% in our largest year-round markets while our more seasonal markets experienced declines of close to 10%. Sales on the irrigation side of the business were up 14% due in part to the gradual recovery of the housing market in some of our key states. Gross profit for the first quarter of 2013 was essentially flat at $104.8 million. Gross profit as a percentage of net sales (gross margin) declined 60 basis points to 28.3% in the first quarter of 2013. This decrease is primarily due to unfavorable product mix as well as competitive pricing pressures. As a result of the slower start to the 2013 season, geographic regions with generally higher margins experienced a proportionally smaller share of our total sales.