Year	Percent
1975-01-01	9.4118900000000000
1976-01-01	7.9961899999999995
1977-01-01	6.7198199999999995
1978-01-01	7.4578700000000000
1979-01-01	8.4443800000000000
1980-01-01	7.9785200000000000
1981-01-01	6.6353700000000000
1982-01-01	5.2940000000000000
1983-01-01	5.6983700000000000
1984-01-01	7.0282100000000005
1985-01-01	10.7657000000000000
1986-01-01	16.5593000000000000
1987-01-01	17.9242000000000000
1988-01-01	18.6356000000000000
1989-01-01	26.6375000000000000
1990-01-01	28.0181000000000000
1991-01-01	26.0454000000000000
1992-01-01	25.4082000000000000
1993-01-01	28.8726000000000000
1994-01-01	33.0062000000000000
1995-01-01	31.4050000000000000
1996-01-01	33.5209000000000000
1997-01-01	40.9082000000000000
1998-01-01	55.0167000000000000
1999-01-01	81.7850000000000000
2000-01-01	100.9010000000000100
2001-01-01	94.0251000000000000
2002-01-01	74.0833000000000000
2003-01-01	68.4685000000000000
2004-01-01	72.2811000000000000
2005-01-01	75.6973000000000000
2006-01-01	90.8005000000000000
2007-01-01	101.1700000000000000
2008-01-01	76.1809000000000000
2009-01-01	62.0229000000000000
2010-01-01	71.3354000000000000
2011-01-01	62.3759000000000000
2012-01-01	60.4968000000000000
2013-01-01	74.1428000000000000
2014-01-01	76.9781000000000000
2015-01-01	78.6146000000000000
2016-01-01	85.8942000000000000
2017-01-01	95.7236000000000000