Year	Percent
1990	0.47482
1991	0.46369
1992	0.45345
1993	0.44194
1994	0.43072
1995	0.96535
1996	0.96922
1997	0.95996
1998	0.93436
1999	0.87595
2000	0.84842
2001	0.8265
2002	0.79903
2003	0.78523
2004	0.7801
2005	0.74283
2006	0.82196
2007	0.77752
2008	0.76755
2009	0.74551
2010	0.74814
2011	0.75144
2012	0.73412
2013	0.72411
2014	0.73222
2015	0.72014
2016	0.71325
2017	0.70139
2018	0.72223
2019	0.7094
2020	0.75714