By Sam Forgione NEW YORK, Jan 23 (Reuters) - Investors in U.S.-based mutual funds pumped $9.32 billion into stock funds in the week ended Jan. 16, the second consecutive week of inflows for such funds, data from the Investment Company Institute showed on Wednesday. The inflows were down from an estimated $14.33 billion the previous week, said ICI, a U.S. mutual fund trade organization. Funds that specialize in U.S. stocks attracted $5.05 billion in new cash in the latest week, down modestly from $7.73 billion the prior week. The interest in stocks marks a sharp turnaround from last year, when investors pulled about $151 billion from stock mutual funds while committing roughly $307 billion to bond mutual funds, according to ICI estimates. The S&P 500 rose a slight 0.8 percent over the reporting period. Several Federal Reserve officials voiced optimism about U.S. economic growth in 2013, while upbeat U.S. retail sales for December and strong corporate earnings for banks JPMorgan Chase and Goldman Sachs boosted sentiment. Investors remained cautious, however, in light of Republican opposition in Congress to increase the $16.4 trillion U.S. debt ceiling. Failure to raise the debt limit could cause the U.S. to default in coming months. Bond funds still posted a strong turnout with inflows of $10.6 billion in the latest week, the most since March of last year. Inflows last week were at $9.42 billion. Hybrid funds, which can invest in stocks and fixed income securities, attracted inflows of $2.12 billion. The gains were down modestly from inflows of $2.8 billion the prior week. The following table shows estimated ICI flows for the past five weeks (all figures in the millions of dollars) : 12/19/12 12/26/12 1/2/13 1/9/2013 1/16/2013 Total Equity -5,315 -4,307 -10,797 14,328 9,317 Domestic -5,289 -3,942 -9,314 7,731 5,046 World -25 -366 -1,483 6,596 4,271 Hybrid* -71 533 -154 2,802 2,122 Total Bond 100 2,532 2,321 9,422 10,599 Taxable 3,368 3,233 2,049 7,041 8,358 Municipal -3,268 -701 272 2,381 2,242 Total -5,285 -1,242 -8,630 26,551 22,039 *Hybrid funds can invest in stocks and/or fixed income securities.