Year	Percent
1991	76.933
1992	76.459
1993	73.412
1994	76.223
1995	76.068
1996	75.033
1997	73.555
1998	75.039
1999	74.073
2000	72.622
2001	72.652
2002	72.434
2003	73.074
2004	72.691
2005	72.035
2006	72.546
2007	73.358
2008	73.718
2009	72.19
2010	74.784
2011	75.353
2012	76.096
2013	75.812
2014	74.865
2015	75.104
2016	74.657
2017	74.831
2018	75.047
2019	75.258
2020	75.442
2021	75.634
2022	75.802