Year	Percent
1973-01-01	7.881900000000000
1974-01-01	6.796539999999999
1975-01-01	11.463600000000000
1976-01-01	17.671400000000000
1977-01-01	20.316800000000000
1978-01-01	21.951600000000000
1979-01-01	22.796300000000000
1980-01-01	27.886100000000000
1981-01-01	32.722300000000000
1982-01-01	51.366800000000000
1983-01-01	57.806800000000000
1984-01-01	44.869600000000000
1985-01-01	41.441200000000000
1986-01-01	36.273700000000000
1987-01-01	29.267900000000000
1988-01-01	30.079700000000000
1989-01-01	32.265200000000000
1990-01-01	27.301000000000000
1991-01-01	22.870800000000000
1992-01-01	21.786600000000000
1993-01-01	22.122600000000000
1994-01-01	21.393600000000000
1995-01-01	23.213400000000000
1996-01-01	24.140400000000000
1997-01-01	26.041300000000000
1998-01-01	35.320400000000000
1999-01-01	46.189700000000000
2000-01-01	48.104200000000000
2001-01-01	56.084400000000000
2002-01-01	71.641000000000000
2003-01-01	63.772300000000000
2004-01-01	40.375800000000000
2005-01-01	29.825100000000000
2006-01-01	28.638500000000000
2007-01-01	27.527900000000000
2008-01-01	28.309900000000000
2009-01-01	27.779900000000000
2010-01-01	24.906500000000000
2011-01-01	25.195999999999998
2012-01-01	26.142500000000000
2013-01-01	27.114700000000000
2014-01-01	28.975400000000000
2015-01-01	31.700400000000000
2016-01-01	32.484900000000000