Marten Transport Ltd (Nasdaq/GS:MRTN) reported a 32.2% increase in net income to $7.2 million for the first quarter ended March 31, 2013, from $5.4 million for the first quarter of 2012. It was the Mondovi WI-based truckload and refrigerated carrier’s 12th consecutive year-over-year increase in quarterly net income.

Operating revenue, consisting of revenue from truckload and logistics operations, rose to $164.5 million in the first quarter of 2013 from $151.5 million in the first quarter of 2012. Operating revenue, net of fuel surcharges, climbed 8.2% to $132.7 million in the 2013 quarter from $122.6 million in the 2012 quarter. Fuel surcharge revenue advanced to $31.7 million for the first quarter of 2013 from $28.8 million in the 2012 quarter.

Operating expenses as a percentage of operating revenue, with both amounts net of fuel surcharge revenue, improved to 90.6% for the first quarter of 2013 from 92.2% for the first quarter of 2012.

Randolph L Marten, chairman and chief executive officer, said, “We were able to demonstrate the strength of our multifaceted business model with a 32.2% improvement in net earnings for the quarter on an 8.6% increase in operating revenue. These gains were in large part driven by Marten Transport’s continued strategic focus on customer solutions, cost efficiencies, and improvements in equipment utilization, with disciplined execution reflecting the talent and teamwork of the people of Marten.”

Marten Transport specializes in transporting and distributing food and other consumer packaged goods that require a temperature-controlled or insulated environment. It offers service in the United States, Canada, and Mexico, concentrating on expedited movements for high-volume customers.

Since 2004, Marten Transport’s results and consolidated financial statements have included the accounts of MW Logistics LLC, or MWL, a third-party provider of transportation logistics services. On March 28, 2013, a member of MWL made a capital contribution to MWL. Accordingly, effective from that date, Marten was no longer the primary beneficiary, deconsolidated MWL, and started accounting for its ownership interest in MWL under the equity method of accounting.