Year	Percent
1960-01-01	21.9359000000000000
1961-01-01	18.4290000000000020
1962-01-01	17.9549000000000000
1963-01-01	16.3901000000000000
1964-01-01	14.4887000000000000
1965-01-01	15.6142000000000000
1966-01-01	14.8829000000000000
1967-01-01	15.5623000000000000
1968-01-01	16.4136000000000000
1969-01-01	17.0353000000000000
1970-01-01	17.2421000000000000
1971-01-01	17.2482000000000000
1972-01-01	16.8491000000000000
1973-01-01	16.2744000000000000
1974-01-01	15.3464000000000000
1975-01-01	15.2256000000000000
1976-01-01	13.2005000000000000
1977-01-01	12.2865000000000000
1978-01-01	12.2564000000000000
1979-01-01	15.0519000000000000
1980-01-01	9.7297300000000000
1981-01-01	8.7074400000000000
1982-01-01	7.8939800000000000
1983-01-01	7.1647200000000000
1984-01-01	6.5025900000000005
1985-01-01	7.1427900000000000
1986-01-01	11.6789000000000000
1987-01-01	13.9612000000000000
1988-01-01	19.8496000000000000
1989-01-01	31.9864000000000000
1990-01-01	25.2630000000000000
1991-01-01	15.9869000000000000
1992-01-01	20.2991000000000000
1993-01-01	26.0750000000000000
1994-01-01	28.3679000000000000
1995-01-01	27.5166000000000000
1996-01-01	31.2419999999999970
1997-01-01	34.5332000000000000
1998-01-01	37.4972000000000000
1999-01-01	39.5908000000000000
2000-01-01	42.5876000000000000
2001-01-01	44.7747000000000000
2002-01-01	43.0450000000000000
2003-01-01	44.6487000000000000
2004-01-01	46.0025000000000000
2005-01-01	49.2096000000000000
2006-01-01	52.7497000000000000
2007-01-01	55.3588000000000000
2008-01-01	57.3394000000000000
2009-01-01	62.4349000000000000
2010-01-01	62.1450000000000000
2011-01-01	64.9359000000000000
2012-01-01	68.6489000000000000
2013-01-01	69.8039000000000000
2014-01-01	71.7572000000000000
2015-01-01	77.5073000000000000
2016-01-01	82.6837000000000000