Yesterday, we reported second quarter net income of $45 million or $0.46 per share, which included after-tax debt refinancing charges of $2.5 million or $0.025 per share. Excluding the refinancing charges, earnings were $48 million or $0.49 per share, which is the second quarter record compared to the second quarter 2011 net income of $40 million or $0.39 per share. Net sales were a record $712 million, up 7% compared to the second quarter of 2011 net sales of $665 million.
The $0.10 per share increase in net income, excluding the refinancing charges, was driven by higher containerboard and corrugated products volume of $0.07; and lower costs for energy, $0.05; recycled fiber, $0.02; chemicals, $0.02; and maintenance, $0.02. These items were partially offset by higher costs for transportation of $0.02; medical, $0.02; depreciation, $0.02; and interest expense, $0.02.
Excluding special items, net income for the first 6 months of 2012 was a record $88 million or $0.91 per share compared to the net income for the first 6 months of 2011 of $79 million or $0.78 per share, excluding special items. Year-to-date net sales were record $1.4 billion compared to the $1.3 billion in 2011.
Overall, we had another strong quarter setting several records and generating earnings, excluding special items, $0.04 per share better than the earnings guidance we provided on April 17.The higher earnings came from better-than-forecasted mill cost and better-than-expected export prices, and better-than-expected mix improvement in the corrugated business. We also achieved all-time record corrugated product shipments and record second quarter mill production despite having 3 of our mills down for their annual maintenance outages during the quarter. In addition to strong operations, we completed important strategic action during the quarter, the refinancing of $400 million in notes due in 2013. Considering the risks and uncertainties in the debt market, we're very pleased to have this refinancing behind us, and Rick West will provide more details on the refinancing later on the call.