Year	Percent
1973-01-01	26.50640000000000
1974-01-01	26.97090000000000
1975-01-01	27.47780000000000
1976-01-01	27.97860000000000
1977-01-01	28.09460000000000
1978-01-01	27.53560000000000
1979-01-01	26.71390000000000
1980-01-01	27.31760000000000
1981-01-01	27.68350000000000
1982-01-01	27.61600000000000
1983-01-01	30.97980000000000
1984-01-01	35.57630000000000
1985-01-01	39.09620000000000
1986-01-01	43.09350000000000
1987-01-01	53.38100000000000
1988-01-01	60.72880000000000
1989-01-01	60.46620000000000
1990-01-01	59.75240000000000
1991-01-01	55.54350000000000
1992-01-01	51.16250000000000
1993-01-01	46.03160000000000
1994-01-01	40.85950000000000
1995-01-01	40.38300000000000
1996-01-01	38.21050000000000
1997-01-01	36.92090000000000
1998-01-01	38.19060000000000
1999-01-01	38.87460000000000
2000-01-01	89.50700000000000
2001-01-01	145.40300000000000
2002-01-01	151.71700000000000
2003-01-01	156.98800000000000
2004-01-01	159.25500000000000
2005-01-01	167.40099999999998
2006-01-01	178.50300000000000
2007-01-01	194.06500000000000
2008-01-01	211.04400000000000
2009-01-01	222.20400000000000
2010-01-01	203.82500000000000
2011-01-01	199.44500000000000
2012-01-01	193.92700000000002
2013-01-01	187.95200000000000
2014-01-01	182.88200000000000
2015-01-01	180.75300000000000
2016-01-01	178.99099999999999