[["", "2012", "2011", "2010"], ["expected volatility", "24.0% ( 24.0 % )", "28.8% ( 28.8 % )", "41.7% ( 41.7 % )"], ["risk-free interest rate", "0.8% ( 0.8 % )", "2.1% ( 2.1 % )", "2.1% ( 2.1 % )"], ["dividend yield", "2.2% ( 2.2 % )", "0.0% ( 0.0 % )", "0.0% ( 0.0 % )"], ["expected life ( years )", "6.1", "6.0", "6.1"]]