When Ohio's Kent State University offered custodial staff the option of working four days a week instead of five to cut commuting costs, most jumped at the chance, part of a US trend aimed at combating soaring gasoline prices.

"We offered it to 94 employees and 78 have taken us up on it," said university spokesman Scott Rainone.

A man fills his truck up with gas at a gas station in Santa Monica, California, May 28, 2008. [Agencies]

The reason is simple: rising gas prices and a desire to retain good workers. And while so far only the university's custodians are eligible, Rainone hopes the option will be offered to all departments -- including his own.

"In our office, we have people who travel anywhere from five or six miles to a couple who are on the road 45 to 50 minutes," Rainone said. "As the price of gas rises, the level of grumbling rises."

Regular gasoline averages $3.94 a gallon in the United States, up 33 cents in the past month and 88 cents since the beginning of the year, the Energy Information Administration said this week.

The federal government has offered four-day workweeks to eligible employees for years as part of a flexible work program that also includes telecommuting.