Year	Percent
1991	50.298
1992	50.077
1993	40.979
1994	40.957
1995	40.266
1996	40.528
1997	40.242
1998	39.122
1999	39.382
2000	39.872
2001	39.035
2002	38.708
2003	39.127
2004	39.07
2005	54.257
2006	40.575
2007	40.364
2008	40.13
2009	39.884
2010	39.432
2011	49.142
2012	48.532
2013	48.165
2014	48.194
2015	51.694
2016	51.985
2017	53.201
2018	53.107
2019	52.953
2020	52.846
2021	52.752
2022	52.657