Year	Percent
1960-01-01	1.9553800000000000
1961-01-01	3.0311100000000000
1962-01-01	3.9212800000000003
1963-01-01	4.8869000000000000
1964-01-01	6.7329200000000000
1965-01-01	6.6217600000000010
1966-01-01	6.3179200000000000
1967-01-01	3.0699200000000000
1968-01-01	4.7930800000000010
1969-01-01	5.9804300000000000
1970-01-01	2.4463000000000000
1971-01-01	2.4038300000000000
1972-01-01	3.6053000000000000
1973-01-01	4.5574000000000000
1974-01-01	5.8736500000000000
1975-01-01	8.2498800000000010
1976-01-01	11.3451000000000000
1977-01-01	14.6845000000000000
1978-01-01	14.7703000000000000
1979-01-01	14.2530000000000000
1980-01-01	13.3628000000000000
1981-01-01	12.2346000000000000
1982-01-01	12.3921000000000000
1983-01-01	12.6918000000000000
1984-01-01	12.4540000000000000
1985-01-01	12.3462000000000000
1986-01-01	13.6468000000000000
1987-01-01	13.9476000000000000
1988-01-01	14.1550000000000000
1989-01-01	14.9312000000000000
1990-01-01	16.2517000000000000
1991-01-01	14.4283000000000000
1992-01-01	11.5193000000000000
1993-01-01	10.1141000000000000
1994-01-01	8.4681000000000000
1995-01-01	6.4176500000000000
1996-01-01	6.4673300000000005
1997-01-01	8.7938200000000000
1998-01-01	10.7228000000000000
1999-01-01	10.0250000000000000
2000-01-01	10.7051000000000000
2001-01-01	11.4985000000000000
2002-01-01	12.4834000000000000
2003-01-01	13.1305000000000000
2004-01-01	13.8660000000000000
2005-01-01	15.1241000000000000
2006-01-01	16.9498000000000000
2007-01-01	16.6535000000000000
2008-01-01	16.5412000000000000
2009-01-01	16.9123000000000000
2010-01-01	16.1621000000000000
2011-01-01	16.9836000000000000
2012-01-01	18.7872000000000000
2013-01-01	22.7173000000000000
2014-01-01	26.5489000000000000
2015-01-01	27.6804000000000000
2016-01-01	26.5608000000000000