Year	Percent
1987-01-01	4.685987787924980
1988-01-01	7.887323943661820
1989-01-01	6.415539634949680
1990-01-01	7.819191447305410
1991-01-01	6.497345559845460
1992-01-01	6.212678644574800
1993-01-01	4.887608396458860
1994-01-01	5.649908939455130
1995-01-01	4.627766599597580
1996-01-01	5.524809860151340
1997-01-01	3.727657601836340
1998-01-01	5.491011803809440
1999-01-01	1.983824272341840
2000-01-01	1.591969174609710
2001-01-01	3.653751839136720
2002-01-01	2.320330059554020
2003-01-01	2.289156626506060
2004-01-01	3.237513940033230
2005-01-01	3.037023326170150
2006-01-01	3.936162599298700
2007-01-01	3.774755279988010
2008-01-01	8.302659834111870
2009-01-01	1.621730140034500
2010-01-01	3.057254670015860
2011-01-01	5.198142928204260
2012-01-01	3.014899503349860
2013-01-01	2.582687661417970
2014-01-01	2.510876332537030
2015-01-01	0.878603714174476
2016-01-01	1.276990944973280
2017-01-01	1.637425972675750