Year	Percent
1974-01-01	1.138300000000000
1975-01-01	17.751800000000000
1976-01-01	30.673000000000002
1977-01-01	40.735100000000000
1978-01-01	41.727800000000000
1979-01-01	49.761700000000000
1980-01-01	60.141900000000000
1981-01-01	74.375200000000000
1982-01-01	91.844100000000000
1983-01-01	91.132800000000000
1984-01-01	84.899300000000000
1985-01-01	87.993400000000000
1986-01-01	90.080300000000000
1987-01-01	94.774200000000000
1988-01-01	118.566000000000000
1989-01-01	144.071000000000000
1990-01-01	139.726000000000000
1991-01-01	122.192000000000010
1992-01-01	118.252999999999990
1993-01-01	113.052000000000000
1994-01-01	117.252999999999990
1995-01-01	137.512000000000000
1996-01-01	144.636000000000000
1997-01-01	145.679000000000000
1998-01-01	145.850000000000000
1999-01-01	135.031000000000000
2000-01-01	123.657999999999990
2001-01-01	117.825000000000000
2002-01-01	120.137000000000000
2003-01-01	124.633000000000000
2004-01-01	114.766000000000000
2005-01-01	113.930000000000000
2006-01-01	121.146000000000000
2007-01-01	122.348999999999990
2008-01-01	125.714000000000000
2009-01-01	122.790000000000000
2010-01-01	108.624000000000000
2011-01-01	95.522200000000000
2012-01-01	84.214500000000000
2013-01-01	76.728800000000000
2014-01-01	74.071900000000000
2015-01-01	72.720000000000000
2016-01-01	74.679500000000000