SPOKANE, Wash.--(BUSINESS WIRE)--Clearwater Paper Corporation (NYSE:CLW) today reported financial results for the first quarter of 2015. The company reported net sales of $434.0 million for the first quarter of 2015, down 10.5% compared to net sales of $484.9 million for the first quarter of 2014 primarily due to the sale of the company’s specialty mills in December 2014. Net earnings determined in accordance with generally accepted accounting principles, or GAAP, for the first quarter of 2015