Year	%
1988	1.59611
1991	1.194451
1993	1.227793
1996	0.6823854
1997	0.4472656
1998	1.25215
1999	1.205437
2000	0.1395397
2001	0.4460493
2002	1.027111
2003	0.5890553
2004	0.0286923
2005	0.6666331
2006	0.4520426
2007	0.1652579
2008	0.0898153
2009	0.0238202
2010	0.017905
2011	0.3063765
2012	0.3163328
2013	0.1179171
2014	0.8232858
2016	0.4396014
2020	0.4121515
2021	0.3812243