Bryan M. Hackworth
Analyst · CJS Securities
Thank you, Paul. As a reminder, our results for the first quarter of 2014, as well as the same period in 2013, will reference adjusted pro forma metrics. First quarter 2014 net sales were $129.8 million, up 13% compared to $114.7 million for the first quarter of 2013. Business category net sales were $118.4 million, up 13%, compared to the first quarter of 2013 net sales of $104.6 million.
Our consumer category net sales were $11.4 million, up 13%, compared to the first quarter of 2013 net sales of $10.1 million. Gross profit for the first quarter was $36.8 million or 28.3% of sales, compared to a gross margin of 28.6% in the first quarter of 2013, while operating expenses were $28 million or 21.6% of sales, compared to $26.5 million or 23.1% of sales in the first quarter of 2013.
Breaking down our operating expenses. R&D expense was $4.3 million, compared to $4.2 million in the first quarter of 2013. SG&A expenses were $23.7 million, compared to $22.3 million in the first quarter of 2013. Operating income was $8.8 million, an increase of 38%, when compared to $6.4 million in the first quarter of 2013.
Effective tax rate was 24.1%, compared to 16.8% in the first quarter of 2013. First quarter of 2014 net income was $6.4 million or $0.40 per diluted share, compared to $4.8 million or $0.32 per diluted share in the first quarter of 2013.
Next I'll review [ph] our cash flow and balance sheet at March 31, 2014. We've generated a significant amount of cash during the past 12 months, as our cash balance has increased to $90.4 million at March 31, 2014, compared to $28.7 million a year prior.
We continue to evaluate the potential uses of our cash, including internal investments, as well as mergers and acquisitions. However, at this time, we believe repurchasing our shares is the best alternative given our bright future and our recent trading price. As a result, our Board of Directors has authorized us to purchase up to 1 million shares. Purchases may be made in open market transactions, block transactions, on or off an exchange or in privately negotiated transactions.
DSOs were approximately 59 days at March 31, 2014, compared to 69 days the year prior. Net inventory turns were approximately 4 turns at March 31, 2014, compared to 3.7 turns the year prior.
Now turning to our guidance. For the second quarter of 2014, we expect revenue between $141 million and $149 million, compared to last year's second quarter revenue of $136.1 million. EPS for the second quarter is expected to range from $0.56 to $0.66 per diluted share, compared to $0.53 recorded for the second quarter of 2013.
I'd now like to turn the call back to Paul.