Low gasoline prices put more money back into U.S. consumers’ wallets. However, the added boost to income has not translated to outsized performance in discretionary stocks and related exchange traded funds as skeptical consumers hold back.

Year-to-date, the Consumer Staples Select Sector SPDR (NYSEArca: XLP) dipped 1.0%, whereas the Consumer Discretionary Select Sector SPDR (NYSEArca: XLY) fell 3.0%. [Listen to What Staples ETFs Have to Say]

Some Americans are splurging with the windfall generated from low gas prices, taking trips and buying something nice, but others may be stowing the cash away in anticipation of higher gasoline prices ahead. [Leisure, Entertainment ETFs: Consumers Spending on ‘Experiences’]

Specifically, according to the monthly University of Michigan survey, consumers expect gasoline prices to rise 20 cents in 2015 and by $1 over the next five years, the largest anticipated rise since January 2009, reports Nina Glinski for Bloomberg. In contrast, gas prices dipped $1.08 over 2014.

“I’m afraid it’s gonna go back up soon,” Evan Lee, a 42-year-old lab manager from Queens, New York, said in a separate Bloomberg article. “This is too good to be true, right?”

The future expectations for gas prices could have also contributed to the restrained spending in December. For instance, household purchases dipped 0.3% in December – the largest drop in five years, durable goods spending declined 0.7% and non-durable goods purchases was down 0.1%.

“Looks like they spent all their gasoline price savings in November, and saved the rest of the gas price tax cut in December,” Chris Rupkey, chief financial economist at Bank of Tokyo-Mitsubishi UFJ, said.

While consumers may be saving more, consumer spending should still slowly rise over 2015 as the U.S. economy improves. According to Goldman Sachs, it takes 12 months for shoppers to start spending their gas savings at stores, which means that retailers could see a boost in July.

“Consumers appear to be saving most of their recent windfall from lower gasoline prices,” Gus Faucher, a senior economist at PNC Financial Services Group, said in a note. “However, consumer spending growth will be solid in 2015 thanks to more jobs, higher wages and lower energy costs. Households will be able to both spend more and save more this year.”

Consumer Discretionary Select Sector SPDR

For more information on consumer spending, visit our consumer discretionary category.

Max Chen contributed to this article.