A seesaw effect: As gas prices fall, consumer confidence grows

While the U.S. economy remains far from robust, two important factors -- falling gas prices and rising consumer confidence -- suggest the nation's economic momentum is picking up.

According to the latest monthly survey by the National Association of Convenience Stores, a trade group representing stores that account for 80 percent of the gas sold in the U.S., 47 percent of all consumers polled said they are optimistic about the economy. That's the highest such level of confidence in 14 months, and up eight percentage points from last month's 10-month low of 30 percent. It's also eight points higher than it was this time in 2013.

Not surprisingly, considering the survey's source, 87 percent of those polled said lower gas prices were also affecting their overall views on the economy. Prices at the pump this year are, on average, double digits lower per gallon than in 2013, according to GasBuddy.com.

"We have seen increasingly wide swings in economic mood over the past three months as consumers continue to sort out how world and national events could affect their economic security," NACS executive Jeff Lenard said in a statement.

"At the same time, he continued, "it appears that what happens at the corner store with gas prices continues to play a major role in consumer sentiment."

Twenty-two percent of those polled said they expect to do more shopping in the coming months, while another 22 percent said they'll shop less. Younger consumers ages 18 to 34 say they plan to shop more in the next month, compared to 12 percent of people ages 50 and older.

One other bright point in the survey: Consumers said they are seeing "tangible signs" that they're getting more value per dollar, especially at the gas pump.

Other measures of the public's mood are also on the rise. The Conference Board said Tuesday that it's index of consumer sentiment rose in August to to 92.4, taking it back to levels before the recession. Forecasters expect that to further help the economy by spurring consumer spending, with Capital Economics senior U.S. economist Paul Dales noting that "higher confidence tends to be accompanied by faster consumption growth.