Year	Percent
1991	49.933
1992	50.408
1993	50.019
1994	49.333
1995	48.752
1996	49.981
1997	50.551
1998	50.833
1999	51.339
2000	51.26
2001	52.236
2002	51.789
2003	53.761
2004	55.091
2005	57.094
2006	56.698
2007	54.443
2008	58.216
2009	59.475
2010	61.522
2011	61.932
2012	62.366
2013	61.752
2014	62.029
2015	60.183
2016	61.033
2017	61.115
2018	61.198
2019	61.317
2020	61.32
2021	61.312
2022	61.368