Thursday is the cheapest day for motorists to fill up at the pump in New Jersey, according to a recent study from

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Sixty-five percent of U.S. states saw cheaper gas prices during the weekend than the week, according to the study that compared trends across the country during a four-year period.

Why are prices cheaper on the weekends?

"Perhaps there's a connection related to the fact that wholesale prices aren't fluctuating over the weekend, nor are oil prices, to the degree that they do during the week," said Patrick DeHaan, senior petroleum analyst with

DeHaan said drivers may also have more time on weekends to comparison shop.

In New Jersey, Sunday was the best day to purchase gas in 2010 and 2011. In 2012 and 2013, Thursday was the best day to fill up. Thursday was also the best time for consumers in Maryland and Delaware.

Gas was cheapest on Mondays for Iowa, Kentucky and Indiana, and only four states saw Tuesday or Wednesday as the best days to purchase gas.

Few states, according to the study, saw consistency year-to-year in the day that featured the best prices.  In fact, only Maryland, South Dakota, Delaware, Indiana and Iowa saw the lowest prices on the same day for three out of the four years the study reviewed.

Lowest Gas Prices in New Jersey
New Jersey Gas Prices provided by