* Bank of America, Citi down after results
* U.S. crude falls more than 4 percent
* Swiss National Bank scraps 3-year euro cap on franc
* Best Buy shares fall
* Indexes off: Dow 0.4 pct, S&P 0.6 pct, Nasdaq 1.1 pct (Updates to early afternoon)
By Caroline Valetkevitch
NEW YORK, Jan 15 (Reuters) - U.S. stocks fell in afternoon trading Thursday, putting them on track for a fifth day of losses, as bank results disappointed and investors fretted over the potential impact of global economic weakness on U.S. earnings.
Oil prices settled down more than 4 percent after weak U.S. economic data spurred worries over oil demand.
"There's a lot of cash still on the sidelines because of the worries over the global economy, over what's going to happen with lower commodity prices," said Eric Marshall, director of research at Hodges Capital Management in Dallas.
The S&P financial sector led the day's decline with a drop of 1.1 percent. Bank of America lost 4.8 percent and was among the S&P 500's biggest drags after the second-largest U.S. bank by assets reported a 14 percent slump in quarterly profit. Citigroup shares fell 3.4 percent after its quarterly results.
Trading will likely remain volatile after the Swiss National Bank scrapped its cap on the franc.
Swiss stocks traded in the United States climbed. Credit Suisse was up 0.7 percent at $22.98 and Novartis jumped 3.3 percent to $100.02 as a strengthening Swiss franc made U.S.-dollar denominated stocks cheaper.
Expectations for U.S. fourth-quarter earnings have been scaled back sharply in recent months, with growth now estimated at 3.5 percent, compared with an Oct. 1 estimate of 11.2 percent growth, according to Thomson Reuters data.
Investors are awaiting not just results but forecasts from companies, Marshall said.
"There's nervousness ... but we think the fourth quarter earnings season will be somewhat of a relief."
At 2:15 p.m., the Dow Jones industrial average fell 65.18 points, or 0.37 percent, to 17,361.91, the S&P 500 lost 11.56 points, or 0.57 percent, to 1,999.71 and the Nasdaq Composite dropped 52.52 points, or 1.13 percent, to 4,586.81.
The benchmark S&P has fallen for four straight sessions and nine of the past 11 days. It is down more about 4 percent from its last record high Dec. 29. The CBOE Volatility index was on track for a fifth day of gains.
Best Buy shares tumbled 10.9 percent as the worst performing S&P 500 component after the electronics retailer posted holiday sales results and said it expects same-store sales growth to be flat to negative in the first two quarters of its fiscal year.
Declining issues outnumbered advancing ones on the NYSE by 1,920 to 1,141, for a 1.68-to-1 ratio; on the Nasdaq, 2,042 issues fell and 655 advanced for a 3.12-to-1 ratio.
The benchmark S&P 500 index was posting 23 new 52-week highs and 14 new lows; the Nasdaq Composite was recording 28 new highs and 110 new lows. (Editing by Bernadette Baum and Nick Zieminski)