The national average price dipped 0.6-cent to $3.848 through Jan. 23.
The national average price increased 2.6 cents to $3.854 through Jan. 16.
Over the last three weeks, the national price has dropped 11.6 cents.
The price for the week ended Dec. 5 fell 3.3 cents to $3.931.
The U.S. average diesel price dropped below $4 a gallon.
Since Oct. 10, the national average price of diesel has climbed 26.6 cents a gallon.
After three weeks of increases, the national average retail price of diesel rose dipped less than a penny to $3.887.
Over the last three weeks, the national average retail price of diesel has climbed 17.1 cents.
Sign up to get Overdrive's daily newsletter.