Year	Percent
1991	45.795
1992	45.976
1993	45.784
1994	45.56
1995	45.338
1996	45.746
1997	46.034
1998	47.032
1999	48.403
2000	47.338
2001	45.659
2002	45.444
2003	47.638
2004	45.728
2005	46.286
2006	47.322
2007	48.003
2008	47.692
2009	46.58
2010	44.918
2011	46.251
2012	47.423
2013	47.673
2014	49.089
2015	50.095
2016	52.145
2017	52.731
2018	52.795
2019	52.787
2020	52.809
2021	52.764
2022	52.646