Year	Percent
1975-01-01	0.4424530000000000
1976-01-01	0.6338070000000000
1977-01-01	0.7795460000000000
1978-01-01	0.8598120000000001
1979-01-01	0.9519780000000001
1980-01-01	1.4996600000000000
1981-01-01	1.2055000000000000
1982-01-01	1.3218000000000000
1983-01-01	1.2352299999999998
1984-01-01	1.0962500000000000
1985-01-01	1.0763300000000000
1986-01-01	0.9117730000000000
1987-01-01	0.9681450000000000
1988-01-01	0.7911950000000000
1989-01-01	0.8948659999999999
1990-01-01	0.7526870000000000
1991-01-01	1.2341799999999998
1992-01-01	1.0189100000000000
1993-01-01	1.2783600000000000
1994-01-01	1.8137200000000000
1995-01-01	1.7506099999999998
1996-01-01	2.2612000000000000
1997-01-01	2.5177800000000000
1998-01-01	2.2801500000000000
1999-01-01	2.4573200000000000
2000-01-01	2.7877400000000003
2001-01-01	2.9799700000000002
2002-01-01	3.0971700000000000
2003-01-01	3.5022300000000004
2004-01-01	2.6798200000000000
2005-01-01	2.7352000000000000
2006-01-01	3.0786800000000000
2007-01-01	3.0985300000000000
2008-01-01	4.2105500000000000
2009-01-01	3.7164800000000002
2010-01-01	3.2282599999999997
2011-01-01	3.4282700000000000
2012-01-01	3.7655400000000000
2013-01-01	3.7684900000000003
2014-01-01	3.4519000000000000
2015-01-01	3.2776800000000000
2016-01-01	2.7589300000000000
2017-01-01	2.6551500000000000