Year	Percent
1960-01-01	3.7309900000000003
1961-01-01	4.1618800000000000
1962-01-01	4.3666800000000010
1963-01-01	5.0626200000000000
1964-01-01	6.1403400000000000
1965-01-01	6.9091800000000000
1966-01-01	7.7064200000000000
1967-01-01	8.6274400000000000
1968-01-01	9.5467900000000000
1969-01-01	10.1533000000000000
1970-01-01	11.2223000000000000
1971-01-01	11.9284000000000000
1972-01-01	12.6152000000000000
1973-01-01	13.5325000000000000
1974-01-01	13.3986000000000000
1975-01-01	13.7578000000000000
1976-01-01	15.3789000000000000
1977-01-01	16.6870000000000000
1978-01-01	17.2345000000000000
1979-01-01	16.0054000000000000
1980-01-01	15.5059000000000000
1981-01-01	15.7616000000000000
1982-01-01	16.0810000000000000
1983-01-01	16.4052000000000000
1984-01-01	14.5059999999999980
1985-01-01	12.4605000000000000
1986-01-01	12.0097000000000000
1987-01-01	11.1988000000000000
1988-01-01	11.5986000000000000
1989-01-01	12.8141000000000000
1990-01-01	14.2678000000000000
1991-01-01	13.9560000000000000
1992-01-01	17.2059000000000000
1993-01-01	19.3045000000000000
1994-01-01	20.9636000000000000
1995-01-01	20.2053000000000000
1996-01-01	19.5879000000000000
1997-01-01	19.7127000000000000
1998-01-01	18.6154000000000000
1999-01-01	18.7256000000000000
2000-01-01	19.0772000000000000
2001-01-01	18.6499000000000000
2002-01-01	17.1495000000000000
2003-01-01	16.0532000000000000
2004-01-01	16.0908000000000000
2005-01-01	15.9270000000000000
2006-01-01	14.9323000000000000
2007-01-01	15.0082000000000000
2008-01-01	16.3649000000000000
2009-01-01	22.0244000000000000
2010-01-01	23.9210000000000000
2011-01-01	25.0041000000000000
2012-01-01	26.3898000000000000
2013-01-01	26.3392000000000000
2014-01-01	28.5325000000000000
2015-01-01	31.2736000000000000
2016-01-01	31.7252000000000000