Year	Percent
1986-01-01	2.76102605011140
1987-01-01	2.79863671804344
1988-01-01	4.02086088985650
1989-01-01	5.25025044815476
1990-01-01	5.97675054881483
1991-01-01	8.04276209834109
1992-01-01	8.28952586622379
1993-01-01	7.63243918967861
1994-01-01	6.49612618708954
1995-01-01	4.96895631912179
1996-01-01	4.84579056314729
1997-01-01	5.25118324018663
1998-01-01	6.08269371650418
1999-01-01	5.52806020870128
2000-01-01	4.61050594034220
2001-01-01	4.07437358984112
2002-01-01	3.93292937193516
2003-01-01	3.55363977341482
2004-01-01	2.85086142464205
2005-01-01	2.59568418067643
2006-01-01	2.56961511559847
2007-01-01	2.28555656174895
2008-01-01	2.63249923249659
2009-01-01	3.89071348029101
2010-01-01	4.23035196214219
2011-01-01	4.12828629435947
2012-01-01	4.51317991101625
2013-01-01	4.08844083095783
2014-01-01	3.78639474714967
2015-01-01	3.77017248308154
2016-01-01	3.55727592090167
2017-01-01	3.20435066570640