Selling and administrative expenses (operating expenses) decreased 3% to $103.5 million in the third quarter of 2012 compared to the same period in 2011. Base business operating expenses were down 6% compared to the third quarter of 2011, as lower employee incentive costs, the impact of currency fluctuations on expenses, the impact of one less selling day and lower bad debt expense more than offset higher professional fees and inflationary increases in other costs.
The Company performed an interim goodwill impairment analysis for its United Kingdom reporting unit during the third quarter and recorded a non-cash goodwill impairment charge equal to the total current goodwill carrying amount of $6.9 million, which had a $0.14 negative impact on diluted EPS for the three and nine months ended September 30, 2012. Adjusted operating income, adjusted net income and adjusted diluted EPS for all periods exclude goodwill impairment and are provided in this release because the company believes these amounts are useful to investors in assessing year-over-year operating performance.
Operating income for the quarter was essentially flat at $41.0 million compared to 2011. Operating income as a percentage of net sales (operating margin) decreased 30 basis points to 7.8% for the third quarter of 2012 compared to the same period in 2011. Adjusted operating income for the quarter increased 17% to $48.0 million and adjusted operating margin increased 100 basis points to 9.1% for the third quarter of 2012 compared to the same period in 2011.
Net income decreased 12% to $21.4 million in the third quarter of 2012, with earnings per share down 10% to $0.45 per diluted share versus $0.50 per diluted share for the third quarter of 2011. Adjusted net income for the third quarter increased 17% to $28.3 million, while adjusted diluted EPS increased 18% to a record $0.59.Net sales for the nine months ended September 30, 2012 increased 8% to a record $1,647.2 million from $1,522.9 million the comparable 2011 period. This growth included a 6% improvement in base business sales despite a 1% unfavorable foreign currency impact. Gross margin decreased approximately 60 basis points to 29.0% in the first nine months of 2012 from 29.6% for the same period last year.