Year	Percent
1991	0.27437
1992	0.34497
1993	0.94386
1994	0.88711
1995	0.80352
1996	0.39162
1997	0.46328
2000	0.45517
2002	0.49804
2004	0.74618
2005	0.37989
2006	0.36778
2007	0.24071
2008	0.25117
2009	0.72503
2010	1.31259
2011	1.2932
2012	1.1975
2013	0.89706
2014	0.77776
2015	0.66714
2016	0.26302
2017	0.27509