July 17 (UPI) -- U.S. retail gasoline prices have remained relatively stable over the last month, though that masks some underlying volatility, analysis finds.
Motor club AAA reported a national average retail price of $2.87 for a gallon of regular unleaded gasoline on Tuesday, relatively stable over the last month. The average price per gallon on this date last month was $2.89 per gallon.
The stability masks big swings in the price for Brent crude oil, a major factor behind the price of gasoline. The price for Brent declined more than 4 percent on Monday, following a 6 percent drop on July 11. Despite those huge swings, Brent is down about 4.6 percent from one month ago.
As gasoline prices moved closer to the $3 per gallon threshold, U.S. President Donald Trump called on members of the Organization of Petroleum Exporting Countries to pump more oil, implicitly to keep consumer prices from going too high.
Patrick DeHaan, the lead petroleum analyst for GasBuddy, said much of the momentum for price was driven by elements outside the United States.
"If there's anything to learn here it's that President Trump has little power over global supply and demand, and if anything, there are few options for the president to bring real change to gas pumps," he said in a statement.
AAA did not publish a regular weekly market report as expected.
By region, the West Coast is the most expensive market in the country. Arizona has the lowest state average price in the region at $3.04 per gallon. Retail gasoline inventories in the region were down about 3 percent from the previous week and 1.7 percent below the five-year average, suggesting demand strains could push the retail price higher.
The Midwest and Great Lakes, meanwhile, is the most volatile market in the country. Michigan has the highest national average there, with the price at the pump up 2.3 percent from last week. Federal data show regional gasoline inventories were lower than last week and lower than the five-year average.
"Two things are for sure in one's lifespan: death and taxes, but you can add uncertainty at the pump, especially this summer," DeHaan added.
The federal government said the national average retail price for a gallon of gas was $2.89 last month. The full-year average forecast is $2.76 for this year and $2.77 for 2019.