Gas prices in the U.S. fell last week below $4 per gallon for the first time since March, bringing a measure of relief to consumers.

Oil prices fell more than 1% on Wednesday, extending this week’s losses to trade near four-month lows on signs that more stranded oil tankers were set to move out of the Strait of Hormuz.

U.S. crude closed at $73.21 Tuesday, just $6.19 higher than the day before the U.S. struck Iran. That’s a drop of more than 36% since their peak in April.

The national average gas price meanwhile hovered at $3.93, according to the AAA tracker, compared to the $4.52 average a month ago. That’s a drop of around 13%.

But that’s still much higher than the national average price a year ago, which stood at $3.22, according to AAA.

Increased gas prices have resulted in higher monthly expenses for Americans — anywhere from less than $20 to more than $300 for a driver who fills up twice a month, according to an NBC News analysis of AAA’s average national gas price data.

Trump sought to reassure voters at a key Pennsylvania swing district on Tuesday that costs are coming down and that they are better off than they were two years ago.

Despite the relative reprieve at the pump, there is still uncertainty about whether the interim agreement will hold and traffic will continue to flow through the key trade route as the parties continue to negotiate the final agreement to settle the thorniest issues, such as Iran’s nuclear program.

The U.S. and Iran were in dispute Tuesday over whether Tehran had agreed to allow U.N. inspections of its nuclear sites.