Year	Percent
1991	52.493
1992	53.055
1993	52.831
1994	52.132
1995	51.882
1996	50.796
1997	50.224
1998	51.012
1999	50.874
2000	51.162
2001	51.295
2002	50.634
2003	50.459
2004	50.275
2005	50.695
2006	50.893
2007	51.042
2008	51.578
2009	51.457
2010	51.531
2011	52.77
2012	53.663
2013	54.313
2014	54.845
2015	54.989
2016	54.805
2017	54.3
2018	53.598
2019	52.931
2020	52.472
2021	52.214
2022	52.192