Year	Percent
1991	74.705
1992	75.416
1993	76.817
1994	78.171
1995	78.901
1996	80.254
1997	80.493
1998	80.921
1999	81.456
2000	80.789
2001	81.135
2002	81.71
2003	82.788
2004	83.56
2005	84.058
2006	85.103
2007	85.452
2008	86.224
2009	87.496
2010	88.029
2011	88.728
2012	88.554
2013	89.302
2014	89.336
2015	89.23
2016	89.441
2017	89.584
2018	89.815
2019	90.044
2020	90.244
2021	90.425
2022	90.553