Maki said gasoline at the pump has already declined $0.50 per gallon since June, and futures suggest prices could fall another 20 percent year over year by March. Gasoline was at $3.02 per gallon nationally Wednesday, according to AAA, and analysts expect it to fall through $3 a gallon nationwide by next week.
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"When consumers are spending less on gasoline, they have more to spend elsewhere," said Maki. "That effect tends to happen quickly in the U.S. partly because consumers don't save very much."
Maki said the effect from lower fuel prices should be around for a while. "Gasoline is about 3 percent of consumer spending so if you crank through the math, that should be about 0.6 rise in consumer income in that year ending in March," he said.
"It's hard to translate real consumer spending numbers into holiday sales," said Maki. "I can say more generally before this happened, I would be looking for a moderate holiday season so I think this similarly raises the risk of a stronger holiday shopping season."
If GDP for the third quarter comes in as expected, and fourth quarter GDP rises above 3 percent, it would be the first time since the recession that the economy grew at more than 3 percent for three quarters in a row.
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"If consumers spend as much as they are happier, then it should be a pretty good fourth quarter," said Rupkey.
Weekly jobless claims data is also reported at 8:30 a.m. Thursday, and it is expected to show 284,000 claims. Improvements in the labor market are behind the sharp jump in consumer confidence reported earlier this week. Consumer confidence rose to 94.5 in October, from 89 in September, the highest level in seven years.
Traders Thursday will also be considering the Fed's more hawkish comments on the jobs market and inflation, which sent markets on a roller coaster ride Wednesday afternoon when its statement was released. Fed Chair Janet Yellen speaks at 9 a.m. ET at the Fed's National Summit on Diversity in the Economics Profession. She is making welcoming remarks, and is not expected to answer questions.
Dozens of earnings are expected, with ConocoPhillips, MasterCard, CME Group, Altria, Royal Dutch Shell, Cardinal Health, Cigna, Public Service, Time Warner Cable, Alcatel-Lucent, Kellogg, Johnson Controls, Teva, Fortress Investment, and Air Products reporting before the open. Starbucks, Microchip Tech, Boston Beer, GoPro, LinkedIn, Groupon and Tesoro report after the closing bell.