UK Stocks-Factors to watch on March 31

March 31 (Reuters) - Britain's FTSE 100 index is seen opening down 14 points, or 0.2 percent, on Thursday, according to financial bookmakers. For more on the factors affecting European stocks, please click on * The UK blue chip index closed up 1.6 percent on Wednesday at 6,203.17, recording its highest closing level of 2016, boosted by the mining sector after Federal Reserve Chair Janet Yellen called for caution on raising interest rates, lifting riskier assets. * U.S FED: Federal