This will get you revved up for a Monday.

Monday tends to be the cheapest day of the week to buy gas, according to a study of fuel prices reported by 60 million consumers across the nation from gas savings app GasBuddy.  That was the case in 36 states in 2016. When Monday wasn’t the cheapest day, Tuesday usually was. “Fueling earlier in the week can result in savings for many motorists,” the study concluded.

Just don’t fuel up on Thursdays, which tends to have the most expensive gas. “If every U.S. motorist bought gasoline on Thursday for an entire year, they’d collectively spend an extra $1.1 billion versus filling up on Monday – the lowest priced day of the week,” the study found. Saturday was the second worst day to fuel up.

Patrick DeHaan, senior petroleum analyst at GasBuddy, says that gas stations likely raise prices on the weekends because they know a lot of motorists hit the road then and “may want to squeeze out a little more margin when travel numbers are better.”

The reason Thursday seems to have high prices may be because an influential report from the Energy Information Administration comes on on Wednesdays and and may push prices higher for Thursday. “ “Since commodities trading isn’t active over the weekend, it typically allows stations to ‘let it ride’ over the weekend, culminating in lower prices by the start of the work week,” he says.