Compared to the first quarter last year, we achieved a 40 basis point improvement in our gross margins as a percent of net sales resulting in a gross margin of about 19.5%. This improvement resulted from selling price increases implemented in the mid-2011 period partially offset by the cost of labor and material compared to the same period a year ago. The decline in our margin sequentially resulted from a combination of the seasonal costs associated with the Chinese New Year holidays and the reduction in the premium priced opportunities.
Our adjusted EBITDA was $33.1 million for the quarter, or 12.6% of net sales. Our adjusted EPS was $0.32 per share for the quarter. Jerry will provide more color commentary on the adjusted EBITDA and adjusted EPS in his comments.
Turning to Slide 5, I wanted to make a few comments about our revenue performance for each market. Automotive continues to be the largest of our end markets representing about 40% of our first quarter net sales. Automotive sales increased 15% year-over-year compared to the first quarter last year. A 3% seasonal decline in automotive sales compared to the immediate preceding quarter was related primarily to the Chinese New Year holiday and the premium sales that we talked about in the fourth quarter. I&I remains our second largest end market at 24% of first quarter net sales. As a reminder, I&I is a catch all category that also includes wind and solar energy, medical, locomotion and other industries. It sustained a demand -- sustained demand from a broad-base of customers as end market compensated for slowing demand from a couple of our larger customers. The acquisition of DDi is expected to deepen our customer base in this end market.