SPOKANE, Wash. -

Amid positive signs of an improving economy this week, experts worry about one looming issue that could bring the economy to a screeching halt, gas prices.

The national average is now $3.81 for a gallon of unleaded. In 2008, when gas reached more than four dollars a gallon, it hit everyone in the wallet and deepened the recession.

Gas prices not only hit people at the pump but just about everything you buy, including pizza.

Drivers at Pizza Rita are paid a dollar per delivery, but when gas prices hit $3.72 in Spokane it doesn't always cover the cost of the trip. It's money out of their pocket and money out of your pocket.

"Gas prices go up, I'm just paying for gas so there's no way around it," Pizza Rita driver Mike Markwardt said.

Markwardt gets paid one dollar for each delivery, which he says was great when gas was around two dollars a gallon. Now that it's up to a $3.72 average in Spokane, it's not as great. He's constantly looking for lower prices.

"I pay close attention to gas prices and where I'm going to go to get gas, because every penny helps," he said.

Markwardt was delivering it was to David Stanzak's house on the lower South Hill Wednesday. Stanzak says he can't afford to tip pizza drivers anymore.

"Because the gas prices, the pizza companies are often charging a delivery charge they didn't charge before. So our tips are going down," Stanzak said.

"Some days you have a good tip day and some days you don't have a good tip day, and those are hard days," Markwardt added.

It's more money out of Markwardt's pocket and other delivery drivers. Money, that may turn them to a new profession.

"When gas prices go up, it comes right from my pocket and I'm like I don't want to deliver anymore, I can't afford to deliver anymore," he said.

According to gasbuddy.com analysts, gas prices in Spokaneare expected to peak between $3.75 and $4.15 in May.