Transportation Services Index strengthened in May

The Transportation Services Index (TSI) in May rose 0.9 percent from April's level to 114.8, according to the U.S. Department of Transportation's Bureau of Transportation Statistics (BTS). On a year-over-year basis, the index increased 1.9 percent.

The Freight TSI in May climbed 1.2 percent from April's level to 114.3. A measure of the month-to-month changes in output from for-hire rail, trucking, inland waterway, pipeline and air freight carriers, the index rose 2.7 percent versus May 2012.

May's index is the highest Freight TSI so far in 2013 and the second highest all-time, exceeded only by the level reached in December 2011, which equalled the January 2005 index, BTS officials said in a press release.

The May increase "was driven by growth in rail and truck shipments, accompanying broader signs of strength in the general economy," they said. "Housing starts grew particularly fast in May, up 6.8 percent, which would be important for the Freight TSI since heavy construction materials produce growth in freight tonnage."

The Passenger TSI in May was flat versus April at 116.2 and up only slightly versus May 2012. The index measures month-to-month changes in travel provided by for-hire air, local transit and intercity rail service providers.