Year	Percent
1991	46.91
1992	47.805
1993	48.867
1994	50.607
1995	51.358
1996	51.173
1997	50.851
1998	47.32
1999	50.971
2000	51.725
2001	51.602
2002	48.935
2003	45.279
2004	45.986
2005	46.766
2006	46.7
2007	47.254
2008	47.792
2009	46.86
2010	48.821
2011	47.278
2012	47.243
2013	48.328
2014	48.638
2015	47.958
2016	49.133
2017	48.99
2018	49.274
2019	49.671
2020	49.984
2021	50.305
2022	50.668