[["", "2012", "2011", "2010"], ["weighted average common shares outstanding for basic computations", "323.7", "335.9", "364.2"], ["weighted average dilutive effect of stock options and restricted stockunits", "4.7", "4.0", "4.1"], ["weighted average common shares outstanding for diluted computations", "328.4", "339.9", "368.3"]]