Year	Percent
1991	53.44
1992	52.634
1993	55.532
1994	58.916
1995	58.799
1996	60.753
1997	62.65
1998	68.827
1999	72.484
2000	76.385
2001	78.387
2002	79.95
2003	79.582
2004	79.717
2005	80.65
2006	81.108
2007	82.337
2008	82.531
2009	82.818
2010	83.794
2011	84.357
2012	84.486
2013	85.244
2014	85.103
2015	85.315
2016	85.328
2017	86.113
2018	86.335
2019	86.577
2020	83.572
2021	84.105
2022	84.703