Year	Percent
1991-01-01	9.00000000000004
1992-01-01	9.48654250617166
1993-01-01	9.67934658067928
1994-01-01	24.57101372756050
1995-01-01	17.28093268145900
1996-01-01	11.33087890572820
1997-01-01	7.08700591205705
1998-01-01	5.97650852141862
1999-01-01	3.97752171325036
2000-01-01	3.20340091563114
2001-01-01	5.18701191944063
2002-01-01	5.11232085453321
2003-01-01	5.09993083318365
2004-01-01	3.17988799351338
2005-01-01	6.39788293897880
2006-01-01	4.63737008585631
2007-01-01	4.54180241170064
2008-01-01	11.95862068965520
2009-01-01	3.78861330914626
2010-01-01	3.51881080417185
2011-01-01	5.05740810549093
2012-01-01	5.98590497324009
2013-01-01	2.60581802719518
2014-01-01	1.85460421340917
2015-01-01	1.44115101708211
2016-01-01	2.15685715830902
2017-01-01	1.42324368506850