We know we're spending more at the pump — an extra $170 each month, a recent report shows — but the cost of the handful of groceries the Deseret News is tracking hasn't moved much since the first of May.

Milk went up 9 cents, or about 3.6 percent, in the past month. But the month before that, the price went down 7 percent because it was on sale. So really, milk's gotten cheaper in the three months we've tracked its price.

Also this month, the price of eggs went down nearly 28 percent because of a four-for-$5 sale at Smith's Marketplace for those with a "Fresh Values" card. For shoppers without a card, the price still went way down — by 15.6 percent.

Blue jeans also were 2 bucks off, a nearly 10 percent reduction. And a Friday night pizza and a movie costs you exactly what it did the first of April.

What's really different is gasoline: up 46 cents in the past month to $3.86 a gallon at a downtown Maverik station. That's a 13.5 percent increase over the month and 21 percent since the first week of April.

The average national price of regular gas crept up to $4 a gallon for the first time over the weekend, AAA and the Oil Price Information Service reported. And prices at the pump are expected to keep climbing.

Lehi resident Dennese Snarr is cutting back on visits and out-of-town activities as a result.

"You can't go as many places," Snarr said as she filled up at a Taylorsville station with two of her granddaughters. "We do more things to stay at home."

Gas prices are responsible for about a $2 increase in the cost of our basket of goods over the past month, which totals $150.44. When we first started tracking prices in April, our basket cost $146.63. The price has risen 2.6 percent since April.

Gasoline prices are putting a dent in families' disposable income, according to a Wells Fargo study released Thursday.

In 2008, a typical Utah family spent $471 a month, or $5,655 a year, on gas. That's 5.9 percent of their income, and $171 more every month than the same family spent on gas three years ago, the study states.

Gas prices also impact grocery store prices. Truckers drive food from fruit growers and other producers to supermarkets. Diesel fuel cost an average of $4.79 a gallon on Friday, according to AAA.

When truckers pay more, so do you.

"I see it big time," especially in produce prices, Taylorsville resident Frank Wilcox said. "I tell you, I would hate to have a large family right now."

Our grocery basket is just one example of what a Utah consumer might buy in a month. A more comprehensive look, the Wells Fargo consumer price index, showed a 2 percent jump on food prices between March and April, and a 5 percent increase since February.

"The cost increases out there are real," Utah Food Industry Association spokesman Dave Davis said.

"It's a competitive market out there, and I'm sure retailers are leery about driving the costs up ... to jump them a significant amount," he said. "Perhaps they jumped significantly (months ago) and are waiting for the next shoe to drop, if you will. Perhaps another is in the works. I don't know that, but that is a possible explanation."

Wells Fargo's Wasatch Front consumer price index for May will be issued Friday.

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