Year	Percent
1991	43.743
1992	43.794
1993	44.49
1994	45.089
1995	46.072
1996	46.604
1997	47.114
1998	48.118
1999	49.436
2000	50.099
2001	51.906
2002	52.51
2003	52.997
2004	54.316
2005	55.204
2006	54.932
2007	54.329
2008	55.248
2009	57.655
2010	58.155
2011	59.446
2012	59.37
2013	61.573
2014	61.818
2015	60.927
2016	60.238
2017	60.337
2018	60.706
2019	60.956
2020	61.221
2021	61.575
2022	61.775