Year	Percent
1980-01-01	1.9866099999999998
1981-01-01	2.4650500000000000
1982-01-01	3.7019000000000000
1983-01-01	4.6853500000000000
1984-01-01	5.9570700000000000
1985-01-01	7.0536600000000010
1986-01-01	6.2954800000000000
1987-01-01	6.6641500000000000
1988-01-01	7.0716399999999995
1989-01-01	7.8064899999999990
1990-01-01	7.8398800000000000
1991-01-01	9.2482899999999990
1992-01-01	8.9128100000000000
1993-01-01	9.9974400000000000
1994-01-01	10.7884000000000000
1995-01-01	10.1094000000000000
1996-01-01	10.4787000000000000
1997-01-01	11.4095000000000000
1998-01-01	13.7061000000000000
1999-01-01	16.2370000000000020
2000-01-01	21.3948000000000000
2001-01-01	26.7722000000000000
2002-01-01	32.1599000000000000
2003-01-01	37.1807000000000000
2004-01-01	40.8006000000000000
2005-01-01	40.8157000000000000
2006-01-01	50.7662000000000000
2007-01-01	54.5161000000000000
2008-01-01	52.0654000000000000
2009-01-01	64.2056000000000000
2010-01-01	65.7541000000000000
2011-01-01	62.2622000000000000
2012-01-01	68.4214000000000000
2013-01-01	66.8900000000000000
2014-01-01	58.9219000000000000
2015-01-01	61.2231000000000000
2016-01-01	60.4630000000000000