Year	Percent
1991	47.466
1992	47.345
1993	45.513
1994	45.387
1995	44.627
1996	44.362
1997	44.761
1998	45.371
1999	44.962
2000	44.889
2001	44.332
2002	43.113
2003	43.47
2004	42.107
2005	41.287
2006	42.285
2007	40.695
2008	44.643
2009	45.702
2010	45.763
2011	45.781
2012	46.699
2013	46.729
2014	46.754
2015	46.894
2016	46.864
2017	46.88
2018	46.832
2019	46.753
2020	46.67
2021	46.592
2022	46.523