Year	Percent
1991	40.014
1992	43.28
1993	44.119
1994	44.115
1995	47.228
1996	50.029
1997	52.821
1998	56.302
1999	61.041
2000	64.212
2001	63.529
2002	64.034
2003	63.492
2004	65.319
2005	69.99
2006	74.461
2007	79.185
2008	82.173
2009	75.885
2010	64.166
2011	62.017
2012	68.112
2013	64.039
2014	64.509
2015	70.328
2016	74.751
2017	74.399
2018	74.557
2019	75.104
2020	75.707
2021	76.303
2022	76.819