Year	Percent
1991	40.064
1992	41.181
1993	42.921
1994	43.588
1995	45.931
1996	45.925
1997	45.987
1998	47.159
1999	46.769
2000	47.228
2001	51.705
2002	51.505
2003	52.905
2004	53.093
2005	52.678
2006	54.119
2007	54.754
2008	56.235
2009	55.656
2010	54.955
2011	60.469
2012	62.129
2013	64.393
2014	61.686
2015	57.577
2016	58.882
2017	59.11
2018	59.479
2019	59.88
2020	60.234
2021	60.523
2022	60.861