Year	Percent
1990	0.71278
1991	1.46268
1992	1.75423
1993	1.52044
1994	1.27326
1995	0.89056
1996	0.80052
1997	0.86068
1998	1.03465
1999	0.9163
2000	0.75827
2001	0.5976
2002	0.55925
2003	0.51184
2004	0.37952
2005	0.32234
2006	0.31383
2007	0.25022
2008	0.23395
2009	0.61771
2010	0.84072
2011	0.80072
2012	1.04299
2013	0.93599
2014	0.89164
2015	0.92089
2016	0.8316
2017	0.87382