Year	Percent
1961-01-01	5.4164100000000000
1962-01-01	15.4220000000000000
1963-01-01	12.5765000000000000
1964-01-01	8.3929900000000000
1965-01-01	8.5647500000000000
1966-01-01	8.4322699999999990
1967-01-01	8.8442200000000000
1968-01-01	9.1788600000000000
1969-01-01	10.4066000000000000
1970-01-01	8.6156399999999990
1971-01-01	11.6993000000000000
1972-01-01	12.7271000000000000
1973-01-01	9.5878000000000000
1974-01-01	6.0262900000000000
1975-01-01	6.6683500000000000
1976-01-01	6.9824399999999995
1977-01-01	8.6184400000000000
1978-01-01	10.8043000000000000
1979-01-01	13.5322000000000000
1980-01-01	18.1094000000000000
1981-01-01	21.9338000000000000
1982-01-01	26.2250000000000000
1983-01-01	24.1727000000000000
1984-01-01	22.3095000000000000
1985-01-01	22.6443000000000000
1986-01-01	23.0330000000000000
1987-01-01	23.0908000000000000
1988-01-01	23.4363000000000000
1989-01-01	24.8153000000000000
1990-01-01	25.8764000000000000
1991-01-01	26.2095000000000000
1992-01-01	27.7486000000000000
1993-01-01	29.6189000000000000
1994-01-01	29.5865000000000000
1995-01-01	29.1346000000000000
1996-01-01	32.9252000000000000
1997-01-01	36.7773000000000000
1998-01-01	41.5986000000000000
1999-01-01	46.2973000000000000
2000-01-01	47.0439000000000000
2001-01-01	47.2442000000000000
2002-01-01	47.1537000000000000
2003-01-01	45.3539000000000000
2004-01-01	42.4522000000000000
2005-01-01	44.3133000000000000
2006-01-01	43.8897000000000000
2007-01-01	46.2483000000000000
2008-01-01	52.9589999999999960
2009-01-01	47.3692000000000000
2010-01-01	37.3438000000000000
2011-01-01	39.1921000000000000
2012-01-01	43.1183000000000000
2013-01-01	46.3394000000000000
2014-01-01	48.7985000000000000
2015-01-01	51.8322000000000000
2016-01-01	54.0592000000000000