Year	Percent
1960-01-01	5.1742099999999995
1961-01-01	6.1818900000000000
1962-01-01	6.0086500000000000
1963-01-01	5.7862200000000000
1964-01-01	5.7862200000000000
1965-01-01	5.7862200000000000
1966-01-01	5.7862200000000000
1967-01-01	5.7862200000000000
1968-01-01	5.7862200000000000
1969-01-01	2.1150100000000000
1970-01-01	3.4699400000000002
1971-01-01	4.6013800000000010
1972-01-01	4.8401500000000000
1973-01-01	4.2137300000000000
1974-01-01	3.4847300000000003
1975-01-01	2.9341700000000000
1976-01-01	3.8465900000000000
1977-01-01	5.0743599999999995
1978-01-01	6.3329100000000000
1979-01-01	6.3304500000000000
1980-01-01	5.3870200000000000
1981-01-01	5.4290500000000000
1982-01-01	5.3587099999999990
1983-01-01	5.1878699999999990
1984-01-01	4.7008300000000010
1985-01-01	4.6230500000000000
1986-01-01	4.7681600000000000
1987-01-01	4.5643800000000000
1988-01-01	3.9350500000000000
1989-01-01	2.5562500000000000
1990-01-01	3.2788600000000000
1991-01-01	5.2379500000000000
1992-01-01	6.3819300000000005
1993-01-01	6.1728200000000000
1994-01-01	5.4189200000000000
1995-01-01	6.3479800000000010
1996-01-01	7.4401199999999990
1997-01-01	7.1209399999999990
1998-01-01	7.7326300000000000
1999-01-01	6.5952199999999990
2000-01-01	7.1192000000000000
2001-01-01	7.6049500000000000
2002-01-01	7.5700699999999990
2003-01-01	5.3681300000000010
2004-01-01	3.4871000000000000
2005-01-01	3.4592300000000002
2006-01-01	3.0744700000000003
2007-01-01	2.7525200000000000
2008-01-01	2.8675100000000000
2009-01-01	2.9613900000000000
2010-01-01	3.8618099999999997
2011-01-01	5.4699599999999995
2012-01-01	7.5968200000000000
2013-01-01	10.4243000000000000
2014-01-01	13.3927000000000000
2015-01-01	16.1439000000000000
2016-01-01	18.7969000000000000