Year	Percent
1979-01-01	2.4185700000000000
1980-01-01	3.7154400000000000
1981-01-01	7.2625899999999990
1982-01-01	11.6745000000000000
1983-01-01	12.3613000000000000
1984-01-01	6.1900200000000000
1985-01-01	1.7644799999999998
1986-01-01	4.2465100000000000
1987-01-01	9.3786700000000000
1988-01-01	8.4525100000000000
1989-01-01	6.3558500000000000
1990-01-01	8.3539600000000000
1991-01-01	10.9839000000000000
1992-01-01	15.7421000000000000
1993-01-01	30.0543000000000000
1994-01-01	35.2057000000000000
1995-01-01	8.3688399999999990
1996-01-01	7.5500300000000005
1997-01-01	9.3549899999999990
1998-01-01	11.2803000000000000
1999-01-01	14.2278000000000000
2000-01-01	18.8368000000000000
2001-01-01	16.4466000000000000
2002-01-01	10.4164000000000000
2003-01-01	11.7472000000000000
2004-01-01	17.8841000000000000
2005-01-01	25.4210000000000000
2006-01-01	34.6722000000000000
2007-01-01	46.7339000000000000
2008-01-01	49.0427000000000000
2009-01-01	40.3834000000000000
2010-01-01	40.8192000000000000
2011-01-01	36.5351000000000000
2012-01-01	23.8057000000000000
2013-01-01	18.8067000000000000
2014-01-01	16.7328000000000000
2015-01-01	16.6826000000000000
2016-01-01	17.1068000000000000
2017-01-01	17.7147000000000000