Knight Transportation Inc. announced that based on the strengthening market and recent trends, the company is updating previously announced first quarter 2015 guidance from $0.26 to $0.29 per diluted share to $0.29 to $0.32 per diluted share.

The company's expected range establishing for the second quarter of 2015 is $0.34 in the low end to $0.37 on the high end per diluted share. The company also updating full year 2015 guidance from $1.32 to $1.36 per diluted share to $1.37 to $1.41 per diluted share. The company also expect tax rate to normalize in 2015 to probably the high 39% range, that 39.5%, to maybe just under 40%, is expectation.