After setting a new record high, a monthly gauge of freight moved by the nation’s for-hire transportation industry retreated, according to new Transportation Department figures.

Freight Transportation Services Index (TSI) fell 1.5% in March from the month before, after reaching an all-time high in February. The March index level registered 124 while the February reading was revised downward to 125.9 from 126.4, still a record, as January was revised up slightly.

When the level of March is compared to the same time in 2016, it is up 3.2%.

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

The March decline was due to decreases in trucking, rail carloads, rail intermodal, and water, while air freight and pipeline grew. It took place against a background of mixed signals in other economic indicators that showed employment and personal income grew while housing starts declined. Also, a measure of industrial production rose by 0.5% in March, but this was entirely due to growth in utilities, as manufacturing output declined.

The 0.5% first quarter decrease in the freight TSI from the previous quarter took place as gross domestic product growth slowed to an annual rate of 0.7% from 2.1% in fourth quarter 2016,

The slowdown in GDP growth in the most recent two quarters was preceded by a third quarter decline in Freight TSI and the rapid GDP growth in the third quarter was preceded by a 2.1% increase in Freight TSI in the second quarter.

Despite these recent economic trends, the freight TSI remains at a historically high level. For all four months from December 2016 through March 2017, it was above the level for all previous months.

The decline in the freight TSI during the first quarter of 2017 was the sixth quarterly decline out of the nine quarters since December 2014. Despite the quarterly declines, the index is 0.6% above the level of December 2014.

According to the Transportation Department, research has shown a clear relationship between economic cycles and the Freight TSI.