Year	Percent
1991	69.208
1992	70.113
1993	69.813
1994	68.666
1995	69.823
1996	77.244
1997	77.143
1998	74.645
1999	71.464
2000	69.497
2001	70
2002	67.109
2003	66.383
2004	68.033
2005	69.254
2006	71.425
2007	73.039
2008	74.111
2009	72.94
2010	74.176
2011	74.662
2012	75.209
2013	74.734
2014	76.057
2015	75.599
2016	74.231
2017	74.172
2018	74.26
2019	74.181
2020	73.98
2021	73.61
2022	73.142