Year	Percent
1991	69.672
1992	70.045
1993	70.437
1994	70.588
1995	70.574
1996	70.743
1997	70.901
1998	70.928
1999	70.965
2000	71.049
2001	71.204
2002	71.26
2003	71.26
2004	71.226
2005	71.182
2006	71.285
2007	71.325
2008	71.331
2009	71.37
2010	71.356
2011	71.44
2012	71.48
2013	71.461
2014	71.378
2015	71.261
2016	71.248
2017	71.236
2018	71.216
2019	71.191
2020	71.163
2021	71.133
2022	71.104