Wall St off on last trading day

NEW YORK (Reuters) - U.S. stocks fell on Friday, the last trading day of a turbulent year, with the broad S&P 500 index on track to end 2011 barely changed from 2010's closing level. Efforts by market participants over the past few days to push the broader index into positive territory for the year were not enough as ongoing uncertainty about the euro zone's debt crisis and fears of a global recession curbed market sentiment. The S&P was up 0.2 percent for the year. Not since 1970 has the index shown such little annual movement in either direction. But the Dow has gained 5. ...