Year	Percent
1991	23.886
1992	29.001
1993	32.623
1994	26.94
1995	27.964
1996	34.23
1997	30.25
1998	27.595
1999	28.239
2000	28.752
2001	29.825
2002	30.79
2003	31.972
2004	32.801
2005	33.248
2006	33.647
2007	35.106
2008	35.461
2009	37.234
2010	36.583
2011	37.95
2012	40.13
2013	41.164
2014	41.735
2015	43.341
2016	44.324
2017	45.255
2018	46.192
2019	46.973
2020	47.857
2021	48.71
2022	49.505