Year	Percent
1991	70.159
1992	68.96
1993	69.884
1994	69.95
1995	68.665
1996	69.951
1997	70.783
1998	72.547
1999	73.104
2000	72.49
2001	72.336
2002	71.827
2003	72.147
2004	71.983
2005	72.399
2006	73.023
2007	73.311
2008	73.746
2009	73.088
2010	73.597
2011	73.841
2012	73.836
2013	73.873
2014	73.198
2015	72.517
2016	72.167
2017	72.081
2018	71.776
2019	71.448
2020	71.102
2021	70.823
2022	70.539