Year	Percent
1960-01-01	9.7011700000000000
1961-01-01	9.4690600000000000
1962-01-01	10.4115000000000000
1963-01-01	14.8998000000000000
1964-01-01	16.0319000000000000
1965-01-01	16.1300000000000000
1966-01-01	16.1569000000000000
1967-01-01	17.5733000000000000
1968-01-01	15.7929000000000000
1969-01-01	14.8893000000000000
1970-01-01	12.9564000000000000
1971-01-01	14.6366000000000000
1972-01-01	13.1755000000000000
1973-01-01	13.6327000000000000
1974-01-01	13.9017000000000000
1975-01-01	15.3462000000000000
1976-01-01	17.2006000000000000
1977-01-01	19.3409999999999980
1978-01-01	22.0416000000000000
1979-01-01	22.4949000000000000
1980-01-01	23.0203000000000000
1981-01-01	23.6811000000000000
1982-01-01	24.9889000000000000
1983-01-01	24.7281000000000000
1984-01-01	21.4978000000000000
1985-01-01	18.9728000000000000
1986-01-01	19.5947000000000000
1987-01-01	23.0346000000000000
1988-01-01	23.0678000000000000
1989-01-01	22.4803000000000000
1990-01-01	23.8421000000000000
1991-01-01	23.1614000000000000
1992-01-01	17.5150000000000000
1993-01-01	10.4948000000000000
1994-01-01	10.2593000000000000
1995-01-01	7.9570399999999990
1996-01-01	7.7263199999999990
1997-01-01	7.0197300000000000
1998-01-01	6.6607899999999995
1999-01-01	7.2937000000000000
2000-01-01	7.7163200000000000
2001-01-01	8.1914100000000010
2002-01-01	8.4425600000000000
2003-01-01	8.8950300000000000
2004-01-01	8.8982700000000000
2005-01-01	8.9719100000000010
2006-01-01	9.1060500000000000
2007-01-01	8.9494300000000000
2008-01-01	9.5491600000000000
2009-01-01	10.2991000000000000
2010-01-01	10.5101000000000000
2011-01-01	11.6533000000000000
2012-01-01	13.0985000000000000
2013-01-01	13.8139000000000000
2014-01-01	14.4326000000000000
2015-01-01	15.4632000000000000
2016-01-01	16.4409000000000000