Year	Percent
1973-01-01	18.65200
1974-01-01	17.69800
1975-01-01	17.99290
1976-01-01	18.44240
1977-01-01	18.33060
1978-01-01	16.52740
1979-01-01	11.13190
1980-01-01	10.90130
1981-01-01	11.75500
1982-01-01	12.60440
1983-01-01	13.77070
1984-01-01	13.58950
1985-01-01	12.67870
1986-01-01	11.42210
1987-01-01	10.03960
1988-01-01	8.08939
1989-01-01	5.79102
1990-01-01	6.22497
1991-01-01	7.09072
1992-01-01	9.25260
1993-01-01	11.29610
1994-01-01	12.82620
1995-01-01	14.88550
1996-01-01	18.82210
1997-01-01	23.19470
1998-01-01	28.60450
1999-01-01	31.27640
2000-01-01	30.26280
2001-01-01	28.42650
2002-01-01	26.04150
2003-01-01	23.93950
2004-01-01	21.10590
2005-01-01	20.60300
2006-01-01	19.50990
2007-01-01	20.47120
2008-01-01	24.26330
2009-01-01	27.51930
2010-01-01	25.82590
2011-01-01	26.86200
2012-01-01	31.87800
2013-01-01	37.25900
2014-01-01	40.51360
2015-01-01	43.78070
2016-01-01	44.61810