Year	Percent
1993	0.87
1994	0.76
1995	0.63
1996	0.61
1997	0.59
1998	0.55
1999	0.68
2000	0.58
2001	0.6
2002	0.66
2003	0.7
2004	0.74
2005	0.73
2006	0.62
2007	0.57
2008	0.54
2009	0.48
2010	0.38
2011	0.42
2012	0.41
2013	0.36
2014	0.4
2015	0.34
2016	0.3
