Year	Percent
1960-01-01	6.25801000000000000
1961-01-01	6.37331000000000000
1962-01-01	8.05327000000000000
1963-01-01	8.39022000000000000
1964-01-01	6.93642000000000000
1965-01-01	7.58091000000000000
1966-01-01	8.41651000000000000
1967-01-01	8.59559000000000000
1968-01-01	7.98710000000000000
1969-01-01	7.62165000000000000
1970-01-01	4.96455000000000000
1971-01-01	4.42715000000000000
1972-01-01	3.72667000000000000
1973-01-01	3.05757999999999970
1974-01-01	2.23644000000000000
1975-01-01	2.19676000000000000
1976-01-01	1.89088000000000000
1977-01-01	1.31087999999999980
1978-01-01	1.06072000000000000
1979-01-01	0.93538500000000000
1980-01-01	0.79992299999999990
1981-01-01	0.74335200000000000
1982-01-01	1.10338000000000000
1983-01-01	2.09105000000000000
1984-01-01	3.52858000000000030
1985-01-01	4.58831999999999950
1986-01-01	4.41018000000000000
1987-01-01	4.46389000000000000
1988-01-01	4.18669000000000050
1989-01-01	3.57746000000000000
1990-01-01	2.83604000000000000
1991-01-01	2.26523000000000000
1992-01-01	1.74679000000000000
1993-01-01	1.26142000000000000
1994-01-01	0.92828199999999990
1995-01-01	0.72478199999999990
1996-01-01	0.62626000000000000
1997-01-01	0.54199700000000010
1998-01-01	0.65660400000000000
1999-01-01	1.22108000000000000
2000-01-01	1.49317000000000000
2001-01-01	1.22917000000000000
2002-01-01	0.99536800000000000
2003-01-01	1.11612999999999980
2004-01-01	0.76372500000000000
2005-01-01	0.57942799999999990
2006-01-01	0.70977800000000000
2007-01-01	0.48805200000000004
2008-01-01	0.27102200000000000
2009-01-01	0.47720900000000000
2010-01-01	0.48757399999999995
2011-01-01	0.23056400000000000
2012-01-01	0.18376600000000000
2013-01-01	0.10115600000000000
2014-01-01	0.03791500000000000
2015-01-01	0.03249400000000000
2016-01-01	0.53801499999999990