Analysts forecast that companies in the S&P 500 will report a 3.2 percent increase in fourth-quarter earnings. Financial firms and consumer-discretionary companies are expected to post the biggest growth, according to S&P Capital IQ.
The Labor Department said consumer prices were flat last month as gas prices sank. The December reading of the consumer price index capped a year of tame inflation. Consumer prices increased just 1.7 percent in 2012, down from 3 percent in 2011.
The report led traders to push up prices for Treasurys, knocking yields down. The 10-year Treasury note's yield slipped to 1.82 percent. The yield, used to set mortgages and a wide variety of other loans, ended Tuesday at 1.84 percent.
Among other companies making news:
— Wendy's rose 4 percent, or 18 cents, to $5.08. The hamburger chain, known for its Frosty shakes and square burgers, earnings topped Wall Street's estimates, even as a key indicator of sales at North American restaurants dipped slightly.
— Chipotle Mexican Grill dropped 6 percent. The burrito chain warned that its quarterly earnings would fall short of previous forecasts because it underestimated the hit it would take from higher food costs. Chipotle's stock lost $16.38 to $280.94.
— Genworth Financial jumped 9 percent, the largest gain in the S&P 500. The financial services company laid out a plan to reorganize its business, including putting its mortgage unit under a new company. Genworth's stock gained 72 cents to $8.85.