Year	Percent
1991	44.874
1992	45.016
1993	45.207
1994	45.105
1995	45.153
1996	45.044
1997	45.041
1998	45.248
1999	45.274
2000	45.186
2001	45.38
2002	45.38
2003	45.323
2004	45.023
2005	45.683
2006	46.028
2007	46.404
2008	45.737
2009	46.402
2010	46.752
2011	47.459
2012	47.125
2013	47.005
2014	47.791
2015	47.799
2016	47.976
2017	48.3
2018	48.731
2019	48.969
2020	49.146
2021	49.306
2022	49.447