Year	Percent
1990	0.63323
1991	0.60479
1992	0.57932
1993	0.58219
1994	0.57644
1995	0.8271
1996	0.81455
1997	0.77904
1998	0.76817
1999	0.76614
2000	0.74137
2001	0.7788
2002	0.75686
2003	0.75499
2004	0.73794
2005	0.71818
2006	0.70367
2007	0.68977
2008	0.71874
2009	0.63572
2010	0.62782
2011	0.61218
2012	0.58378
2013	0.56324
2014	0.5427
2015	0.52622
2016	0.52304
2017	0.6747
2018	0.62207
2019	0.31669
2020	0.31052