Year % (cumulative) 1981 17.7000007629395 2000 31.0699996948242 2002 31.2736206054688 2006 37.6500015258789 2012 43.3651809692383 2013 44.5458297729492 2014 43.0400009155273 2015 43.4458503723145 2019 50.8050003051758