Separate gauges of truckload line haul rates and intermodal rates both fell in May, according to newly released figures, following a Monday report showing freight levels are well below those of the last several years.

The Cass Truckload Linehaul Index fell another 1.2% year over year in May after declines of 0.6% and 2.3% in March and April respectively. The latest reading of 121.3 is the lowest since August 2014. May fell 1.3% from the month before and the April reading dropped 2.2% from March.

“With three consecutive months of price declines, the domestic truckload market continues to face softer demand and excess capacity,” said the investment firm Avondale Partners, which provides analysis of the report.

It cited driver pay increases, overall fleet growth, reduction in carrier bankruptcies, and an easing of the 34-hour restart rule as some of the contributing factors.

The index is an indicator of market fluctuations in per-mile truckload pricing that isolates the linehaul component of full truckload costs from other components, such as fuel and accessorials, providing a look at trends in baseline truckload prices.

Meantime, the Cass Intermodal Price Index fell another 2% year-over-year in May, representing 17 consecutive months of year-over-year declines. The latest reading of 126.5 follows an April to May drop of 2.4% and is at its lowest level since February.

Avondale Partners reiterated in its monthly report that intermodal rates are expected to continue declining for the remainder of 2016 “as the dramatic drop in diesel prices … takes its toll on U.S. domestic demand.”

Although they predict that domestic containers may grow in the mid to low single digits through 2016, Avondale added “that is dependent upon demand in longer lengths of haul growing fast enough to offset the loss of volume in shorter lengths of haul, particularly in the East.”

The Cass Intermodal Price Index is an indicator of market fluctuations in per-mile U.S. domestic intermodal costs that includes all costs associated with the move, such as linehaul, fuel and accessorials.

Data within both measures is derived from actual freight invoices paid on behalf of clients of payment processor Cass Information Systems, which totaled $25 billion in 2015.

The reports come on the heels of the release of the Cass Freight Index for May showing that despite freight shipments that were the best since November, spending on freight shipments fell to its lowest level since January.