Year	Percent
1991	67.313
1992	66.274
1993	66.375
1994	64.888
1995	68.954
1996	71.276
1997	70.85
1998	71.581
1999	70.606
2000	73.604
2001	74.197
2002	71.051
2003	71.362
2004	71.296
2005	70.911
2006	72.207
2007	73.135
2008	73.588
2009	74.872
2010	76.143
2011	77.247
2012	81.478
2013	82.117
2014	82.851
2015	83.295
2016	84.482
2017	84.298
2018	84.402
2019	84.561
2020	84.818
2021	85.036
2022	85.221