The average price of diesel in the U.S. has fallen below $2 per gallon for the first time in more than 10 years.

According to data from the U.S. Energy Information Administration, the average on-highway retail price for diesel was $1.980 per gallon as of Monday, down $0.028 from a week earlier and $0.885 from a year earlier.

The U.S. average for diesel was last below $2 per gallon in February 2005. The national average has been on the decline since March 2014, when it peaked at $4.021 per gallon.

Energy Information Administration officials said that they expect diesel prices to stay relatively low over the next two years. Last week, the agency projected that diesel will average $2.22 per gallon in 2016 and $2.58 per gallon in 2017. The 2015 average for diesel was $2.71.

Meanwhile, the U.S. average retail price for gasoline was $1.724 per gallon as of Monday, down $0.035 from a week earlier and $0.550 from a year earlier.