Year	Percent
1983-01-01	753.64399999999990
1984-01-01	606.52699999999990
1985-01-01	479.00500000000000
1986-01-01	438.41800000000000
1987-01-01	539.54800000000000
1988-01-01	421.84400000000000
1989-01-01	392.51099999999997
1990-01-01	422.71100000000000
1991-01-01	499.23800000000006
1992-01-01	421.40900000000000
1993-01-01	450.56400000000000
1994-01-01	496.31400000000000
1995-01-01	449.03200000000000
1996-01-01	450.98600000000000
1997-01-01	581.11900000000000
1998-01-01	436.06800000000004
1999-01-01	390.83200000000000
2000-01-01	387.89099999999996
2001-01-01	356.61000000000000
2002-01-01	322.70799999999997
2003-01-01	370.74100000000000
2004-01-01	399.45500000000000
2005-01-01	432.33900000000000
2006-01-01	542.47100000000000
2007-01-01	521.30099999999990
2008-01-01	483.45700000000000
2009-01-01	653.25100000000000
2010-01-01	653.82700000000000
2011-01-01	595.95000000000000
2012-01-01	626.56800000000000
2013-01-01	690.84200000000000
2014-01-01	650.09300000000010
2015-01-01	669.55700000000000
2016-01-01	626.54199999999990