Year	Percent
1991	49.986
1992	48.804
1993	47.966
1994	48.585
1995	44.337
1996	51.988
1997	55.922
1998	59.094
1999	58.201
2000	60.716
2001	58.684
2002	55.8
2003	55.623
2004	52.536
2005	52.543
2006	52.208
2007	53.228
2008	56.838
2009	51.041
2010	50.226
2011	49.306
2012	50.413
2013	49.851
2014	48.298
2015	49.258
2016	47.12
2017	47.607
2018	47.783
2019	47.629
2020	47.28
2021	46.823
2022	46.314