Year	Percent
1978-01-01	0.56766400000000010
1979-01-01	0.49559899999999996
1980-01-01	2.62860999999999970
1981-01-01	4.68784000000000050
1982-01-01	4.64202000000000000
1983-01-01	2.94232000000000000
1984-01-01	2.48155000000000000
1985-01-01	0.18763200000000000
1986-01-01	0.21906199999999998
1987-01-01	0.25679900000000000
1988-01-01	0.21438800000000002
1989-01-01	0.17476400000000000
1990-01-01	7.63157000000000000
1991-01-01	7.88116000000000000
1992-01-01	6.62477000000000000
1993-01-01	5.92411000000000000
1994-01-01	5.89497000000000000
1995-01-01	5.34157000000000000
1996-01-01	4.71670000000000000
1997-01-01	4.12681000000000000
1998-01-01	4.63378000000000100
1999-01-01	6.55836000000000000
2000-01-01	7.81965000000000000
2001-01-01	8.74108000000000000
2002-01-01	9.81533000000000000
2003-01-01	10.20010000000000000
2004-01-01	9.98393999999999900
2005-01-01	9.27218000000000000
2006-01-01	8.18568000000000000
2007-01-01	6.91747000000000000
2008-01-01	5.38988000000000100
2009-01-01	4.41720000000000000
2010-01-01	3.62235000000000000
2011-01-01	3.19430999999999980
2012-01-01	5.05669000000000100
2013-01-01	10.17190000000000000
2014-01-01	11.35110000000000000
2015-01-01	12.30850000000000000
2016-01-01	12.62290000000000000