The overall consumer price index rose 0.1 percent in September and the core index, which excludes volatile food and energy prices, remained unchanged for the second straight month. Economists polled by Reuters had expected overall prices to rise 0.2 percent and the core consumer price index to rise 0.1 percent in September.
Consumer prices over the past year also rose slightly slower than expected. Overall prices rose 1.1 percent from a year ago, compared to a 1.2 percent forecast. Core prices rose 0.8 percent over the past 12 months, a tick below the 0.9 percent predicted.
The Labor Department said food costs rose 0.3 percent in September, the fastest pace since October 2008. Energy prices rose 0.7 percent from August after rising 2.3 percent in August and 2.6 percent in July. Energy prices have risen 3.8 percent in the past year.
In a separate report, the department said real average weekly earnings fell 0.1 percent in September to $355.04. Economists polled by Reuters had expected earnings to remain unchanged in the month.