If you’re traveling by car this holiday season, you are likely to notice a dramatic tumble in gas prices.

It was just a year ago when Maricopa gas prices eclipsed $5 a gallon.

Gas prices Wednesday in Maricopa ranged between a low of $3.29 per gallon and $3.79 per gallon, Gasbuddy.com showed.

A year ago, one station sold unleaded gas for $5.29 a gallon. At the most expensive gas pumps, that’s about $1.50 less today.

Maricopa’s pump prices follow the trend in metro Phoenix. But the city’s prices are not nearly as low Casa Grande, Gasbuddy.com price listings show.

Gas prices this month in 2021 posted an average price of $3.74 in Arizona, much closer to today’s statewide average of $3.63 a gallon.

The state’s north-south price line appears to be drawn at Casa Grande, where gas prices dip to $2.75 per gallon. Further south in Pima County, Tucson gas prices are as low as $2.83 per gallon.

To the north in Maricopa County, pump prices rise, but are far lower than this time last year when motorists were filling up for $5 or more per gallon.

Now, the nearby town of Eloy has Arizona’s rock-bottom gas prices, as low as $2.71 per gallon, Gasbuddy reports.

Phoenix prices Wednesday ranged from $3.13 to $4.19 per gallon. Chandler prices varied from $3.45 to $3.99 per gallon.

So, why the gas-price decline?

Patrick De Haan, head of petroleum analysis at Gasbuddy.com, says there are a few variables at play. They include seasonal falling demand, refinery locations and a much lower cost of a barrel of West Texas crude oil. West Texas crude was at $76.93 per barrel, about 13% lower than the same time last year.

Plus, De Haan said, it can come down to a number of gas stations competing for customers in a designated area.

In Eloy’s case, there’s a battle of the pumps at four stations, all priced at $2.71 per gallon.

The price of gas from different refineries can also make a difference in pump prices.

“The Phoenix market gets much of its gas from refineries in California, while further south in Arizona, Tucson gets much of its gas from Texas refineries,” De Haan told InMaricopa.

California refinery prices tend to be noticeably higher than those in Texas, he said.

Arizona is about 22 cents above the national average gas prices, De Haan said.

For the ninth consecutive week, the U.S. average gas price declined, falling 6.2 cents from a week ago to $3.27 per gallon, according to GasBuddy data compiled from more than 12 million individual price reports covering more than 150,000 gas stations across the country.

The national average is down 25.9 cents from a month ago and 36.9 cents per gallon lower than a year ago. The national average price of diesel has fallen 6.9 cents in the past week and stands at $4.28 per gallon — $1.02 lower than a year ago.