The amount of freight moved by the nation’s for-hire sector fell in both the final month of last year and all of 2015, according to the U.S. Transportation Department.

The Freight Transportation Services Index declined 0.4% in December from November, the second consecutive monthly decline and the first back-to-back drop since February 2015, while it was 2.3% below the all-time high level of 123.8 in November 2014.

The November index was revised downward to 121.5 from 122.0 in last month’s release with smaller downward revisions for August through October.

For all of 2015 the index measured 121, down 2% from the year before and the first year-over-year decline since 2012, when it registered 112.2, but is up from a reading of 118.2 in 2013.

The December decline was broad in terms of the different transportation modes with all of them falling except for trucking, which increased slightly, according to the department. The decrease was driven by weakness in the mining, including oil and gas well drilling and servicing, utility and manufacturing sectors of the economy.

The fourth-quarter TSI decline of 1.2% from the third quarter matched trends in the larger economy and the largest quarterly decline since the first quarter of 2012. Gross Domestic Product (GDP) growth decreased to the relatively slow quarterly rate of 0.2% (which is equivalent to an annual rate of 0.7%) while a measure of industrial production  also declined during the fourth quarter. The freight TSI also declined in three of the four quarters of 2015.

The Freight TSI measures the month-to-month changes in freight shipments by mode of transportation in tons and ton-miles, which are combined into one index. The index measures the output of the for-hire freight transportation industry and consists of data from for-hire trucking, rail, inland waterways, pipelines and air freight.