Year	Percent
1991	35.046
1992	34.046
1993	37.317
1994	32.316
1995	33.705
1996	35.87
1997	36.686
1998	36.821
1999	36.492
2000	40.09
2001	41.458
2002	42.506
2003	43.439
2004	44.301
2005	46.321
2006	46.01
2007	46.856
2008	48.806
2009	43.095
2010	43.511
2011	43.637
2012	43.627
2013	44.623
2014	46.571
2015	48.1
2016	48.199
2017	47.905
2018	47.939
2019	48.013
2020	48.27
2021	48.393
2022	48.809