Core prices, which exclude food and energy items, held steady, but fuel costs rose 4.7 percent month to month after rising 6.4 percent in August.
Investors remained cautious despite the European Union winning the Nobel Peace Prize. A Standard & Poor's downgrade of Spanish debt this week kept investors on edge.
The Dow Jones industrial average was up 37 points early, then down about 20 before barely edging back into positive territory by the close, adding 2.46 points or 0.02 percent to 13,328.85. The Dow dropped 283.39 points Monday through Thursday.
On the New York Stock Exchange, 1,095 issues advanced, while 1,878 declined on volume of 3.14 billion shares.
The Nasdaq composite index, down 86.78 points in the previous four sessions, gave up 5.30 points or 0.17 percent to 3,044.11. The Standard and Poor's 500 index was down 4.25 points or 0.3 percent to 1,428.59, on top of of the 28.09 points shed this week.
The benchmark 10-year treasury note rose 4/32 to yield 1.663 percent.
The euro rose to $1.295 from Thursday's $1.2928. Against the yen, the dollar rose to 78.46 yen from 78.37 yen.
In Japan, the Nikkei 225 index shed 0.15 percent, 12.66 points, to 8,534.12.
In London, the FTSE 100 index dropped 0.62 percent, 36.43, to 5,793.32.