Primarily refrigerated freight hauler Marten Transport on Tuesday reported an increase in net income to $7.9 million, or 24 cents per diluted share, in the second quarter of the year, up from $7.7 million, or 23 cents per diluted share, in the second quarter of 2013.

For the six-month period ended June 30, net income for the Wisconsin-based operation was $13.2 million, or 39 cents per diluted share, compared with $14.9 million, or 45 cents per diluted share, in the 2013 six-month period.

Operating revenue, consisting of revenue from truckload and logistics operations, increased to $168.4 million in the second quarter from $161.4 a year earlier, and increased to $327.8 million in the 2014 six-month period from $325.9 million during the same time in 2013.

Total truckload revenue, including fuel surcharge increased 1.8% in the second quarter compared to a year earlier, totaling $129.1 million, while truckload operating income increased 4.1% during the same time, hitting $11.8 million.

“We remain confident that we are well positioned for the remainder of 2014 and beyond with our rate initiatives that will continue through this year’s third quarter, as the operating environment is becoming more favorable with tightening capacity,” said Chairman and Chief Executive Officer Randolph L. Marten. “We are encouraged by our strong June 2014 performance with net income for the month of $3.1 million, and our opportunity for further profitability growth with our diverse service infrastructure. We continue to drive gains in our key operating measures as our revenue per tractor increased 4.1% over the second quarter of 2013, our seventeenth consecutive quarterly increase.”

Further details are on the Marten Transport website.