Year	Percent
1974-01-01	26.33050000000000
1975-01-01	28.14710000000000
1976-01-01	31.34360000000000
1977-01-01	39.21220000000000
1978-01-01	43.93600000000001
1979-01-01	46.03110000000000
1980-01-01	49.40430000000000
1981-01-01	55.08030000000000
1982-01-01	60.44610000000000
1983-01-01	62.19780000000000
1984-01-01	67.59120000000000
1985-01-01	74.98120000000000
1986-01-01	73.17210000000000
1987-01-01	73.64710000000000
1988-01-01	77.70380000000000
1989-01-01	79.64570000000000
1990-01-01	81.65800000000000
1991-01-01	74.77590000000000
1992-01-01	66.72050000000000
1993-01-01	67.30880000000000
1994-01-01	66.38570000000000
1995-01-01	75.16600000000000
1996-01-01	84.98840000000000
1997-01-01	87.45710000000000
1998-01-01	89.71760000000000
1999-01-01	87.64150000000000
2000-01-01	83.48970000000000
2001-01-01	72.34820000000000
2002-01-01	66.26990000000000
2003-01-01	65.11430000000000
2004-01-01	64.91860000000000
2005-01-01	66.59490000000000
2006-01-01	67.97570000000000
2007-01-01	69.58620000000000
2008-01-01	72.10350000000000
2009-01-01	79.53030000000000
2010-01-01	88.37650000000000
2011-01-01	90.13950000000000
2012-01-01	88.24930000000000
2013-01-01	84.90580000000000
2014-01-01	84.07690000000000
2015-01-01	85.84740000000000
2016-01-01	87.96430000000000