Year	Percent
1983-01-01	41.3757000000000000
1984-01-01	35.0774000000000000
1985-01-01	36.8866000000000000
1986-01-01	32.4228000000000000
1987-01-01	30.0717000000000000
1988-01-01	25.4458000000000000
1989-01-01	18.3327000000000000
1990-01-01	7.6017199999999990
1991-01-01	6.3887400000000000
1992-01-01	6.0385100000000000
1993-01-01	5.6095500000000000
1994-01-01	5.8758000000000000
1995-01-01	5.3792800000000005
1996-01-01	5.5940699999999990
1997-01-01	6.3733800000000000
1998-01-01	7.8367500000000000
1999-01-01	9.0592800000000010
2000-01-01	10.3481000000000000
2001-01-01	11.2107000000000000
2002-01-01	17.3342000000000000
2003-01-01	17.3937000000000000
2004-01-01	17.5079000000000000
2005-01-01	17.2262000000000000
2006-01-01	30.2118000000000000
2007-01-01	33.7498000000000000
2008-01-01	30.9510000000000000
2009-01-01	30.3609000000000000
2010-01-01	25.3108000000000000
2011-01-01	24.9416000000000000
2012-01-01	23.3799000000000000
2013-01-01	22.6916000000000000
2014-01-01	22.8721000000000000
2015-01-01	22.7901000000000000
2016-01-01	21.8184000000000000