Year	Percent
1960-01-01	2.3957500000000000
1961-01-01	2.6503000000000000
1962-01-01	2.5341500000000000
1963-01-01	2.3955000000000000
1964-01-01	2.4365300000000000
1965-01-01	2.4237599999999997
1966-01-01	2.4490000000000000
1967-01-01	2.5913100000000000
1968-01-01	2.9155900000000003
1969-01-01	2.7675500000000000
1970-01-01	2.8563300000000000
1971-01-01	3.0023100000000000
1972-01-01	3.8560500000000000
1973-01-01	4.8320600000000000
1974-01-01	5.5688900000000010
1975-01-01	6.5710800000000000
1976-01-01	7.6970199999999990
1977-01-01	9.9306900000000000
1978-01-01	11.3400000000000000
1979-01-01	11.8185000000000000
1980-01-01	12.3179000000000000
1981-01-01	12.8094000000000000
1982-01-01	12.9408000000000000
1983-01-01	13.2483000000000000
1984-01-01	12.7499000000000000
1985-01-01	12.6519000000000000
1986-01-01	12.6409000000000000
1987-01-01	26.7617000000000000
1988-01-01	45.4377000000000000
1989-01-01	53.0738000000000000
1990-01-01	55.0895000000000000
1991-01-01	63.8960000000000000
1992-01-01	83.1205000000000000
1993-01-01	71.6004000000000000
1994-01-01	29.4122000000000000
1995-01-01	22.7904000000000000
1996-01-01	22.4179000000000000
1997-01-01	23.4666000000000000
1998-01-01	23.4945000000000000
1999-01-01	25.1643000000000000
2000-01-01	27.2237000000000000
2001-01-01	29.1956000000000000
2002-01-01	30.8276000000000000
2003-01-01	35.3934000000000000
2004-01-01	35.4739000000000000
2005-01-01	32.2059999999999960
2006-01-01	30.6202000000000000
2007-01-01	29.0790000000000000
2008-01-01	29.8142000000000000
2009-01-01	30.0547000000000000
2010-01-01	36.9500000000000000
2011-01-01	37.9073000000000000
2012-01-01	36.8745000000000000
2013-01-01	35.7730000000000000
2014-01-01	35.6741000000000000
2015-01-01	38.1228000000000000
2016-01-01	40.7163000000000000