Year	Percent
1973-01-01	35.7749
1974-01-01	41.6229
1975-01-01	48.3552
1976-01-01	55.4098
1977-01-01	58.9068
1978-01-01	69.8053
1979-01-01	75.4384
1980-01-01	77.8714
1981-01-01	80.1591
1982-01-01	88.2455
1983-01-01	87.1071
1984-01-01	88.1983
1985-01-01	101.2550
1986-01-01	97.7672
1987-01-01	96.4737
1988-01-01	96.1030
1989-01-01	96.3353
1990-01-01	88.8879
1991-01-01	82.0516
1992-01-01	79.6771
1993-01-01	82.3360
1994-01-01	80.1693
1995-01-01	78.0267
1996-01-01	79.3704
1997-01-01	79.1029
1998-01-01	77.2206
1999-01-01	79.4936
2000-01-01	78.1198
2001-01-01	83.6831
2002-01-01	89.5692
2003-01-01	90.2001
2004-01-01	86.8226
2005-01-01	89.0396
2006-01-01	89.9754
2007-01-01	93.2223
2008-01-01	100.7510
2009-01-01	98.7058
2010-01-01	96.3667
2011-01-01	97.9238
2012-01-01	86.0952
2013-01-01	73.3163
2014-01-01	73.0343
2015-01-01	73.3186
2016-01-01	73.4560