Year	Percent
1977-01-01	0.18896900000000000
1978-01-01	0.23132700000000000
1979-01-01	0.18574600000000000
1980-01-01	0.11697600000000000
1981-01-01	0.08918900000000000
1982-01-01	0.08918900000000000
1983-01-01	0.08918900000000000
1984-01-01	0.08918900000000000
1985-01-01	0.08918900000000000
1986-01-01	0.08918900000000000
1987-01-01	0.08918900000000000
1988-01-01	0.08918900000000000
1989-01-01	0.42204300000000000
1990-01-01	0.49702700000000005
1991-01-01	0.48688500000000000
1992-01-01	0.44985900000000000
1993-01-01	3.53078000000000050
1994-01-01	3.35046999999999960
1995-01-01	3.43455000000000000
1996-01-01	3.67671000000000000
1997-01-01	4.05636999999999900
1998-01-01	4.04496000000000000
1999-01-01	3.81785000000000000
2000-01-01	2.91554000000000000
2001-01-01	3.71496999999999970
2002-01-01	3.71894000000000040
2003-01-01	3.29885000000000000
2004-01-01	4.67244000000000000
2005-01-01	7.61999000000000000
2006-01-01	16.69390000000000000
2007-01-01	22.78530000000000000
2008-01-01	20.96050000000000000
2009-01-01	33.22100000000000000
2010-01-01	30.31699999999999700
2011-01-01	28.79550000000000000
2012-01-01	29.94710000000000000
2013-01-01	31.66380000000000000
2014-01-01	30.71620000000000000
2015-01-01	36.81920000000000000
2016-01-01	44.00199999999999500