Year	Percent
1983	0.34091
1984	0.4775
1985	0.55123
1986	0.56394
1987	0.63109
1988	0.81053
1989	0.95839
1990	1.09274
1991	0.57891
1992	0.49026
1993	0.33858
1994	0.31037
1995	0.36725
1996	0.46328
1997	0.51969
1998	0.48193
1999	0.43193
2000	0.42451
2001	0.35703
2002	0.39072
2003	0.41021
2004	0.3337
2005	0.47825
2006	0.42535
2007	0.56918
2008	1.77719
2009	0.78781
2012	1.22435
2013	1.14837
2014	1.71942
2015	1.48103