Year % (cumulative) 1976 29.1667308807373 1992 52.8932609558105 2000 50.0499992370605 2001 48.4700012207031 2002 46.6699981689453 2004 48.3300018310547 2005 51.8600006103516 2006 51.7000007629395 2007 57.6399993896484 2008 56.1399993896484 2009 57.6599998474121 2011 60.1100006103516 2012 62.9900016784668 2013 64.4400024414062 2014 60.1800003051758 2015 62.3499984741211 2016 63.5 2017 62.7400016784668 2018 64.870002746582 2019 68.2200012207031 2020 67.3000030517578 2021 69.5199966430664 2022 66.4788360595703