Year	Percent
1968-01-01	0.000531000000000000
1969-01-01	0.000482000000000000
1970-01-01	0.000446000000000000
1971-01-01	0.024712000000000000
1972-01-01	0.061703999999999995
1973-01-01	1.332150000000000000
1974-01-01	1.078930000000000000
1975-01-01	4.115320000000000000
1976-01-01	5.864759999999999500
1977-01-01	7.345590000000000000
1978-01-01	9.515419999999999000
1979-01-01	7.686450000000000000
1980-01-01	8.524300000000000000
1981-01-01	9.057860000000000000
1982-01-01	11.708000000000000000
1983-01-01	12.674100000000000000
1984-01-01	12.416700000000000000
1985-01-01	8.903490000000000000
1986-01-01	7.366569999999999000
1987-01-01	6.798230000000000000
1988-01-01	6.610020000000000000
1989-01-01	8.861369999999999000
1990-01-01	10.077100000000000000
1991-01-01	9.658160000000000000
1992-01-01	9.658160000000000000
1993-01-01	9.658160000000000000
1994-01-01	9.658160000000000000
1995-01-01	9.658160000000000000
1996-01-01	9.658160000000000000
1997-01-01	9.658160000000000000
1998-01-01	9.658160000000000000
1999-01-01	9.658160000000000000
2000-01-01	9.658160000000000000
2001-01-01	9.658160000000000000
2002-01-01	9.658160000000000000
2003-01-01	9.658160000000000000
2004-01-01	9.658160000000000000
2005-01-01	23.536600000000000000
2006-01-01	16.728700000000000000
2007-01-01	15.387800000000000000
2008-01-01	14.721600000000000000
2009-01-01	15.774900000000000000
2010-01-01	13.836800000000000000
2011-01-01	11.923700000000000000
2012-01-01	11.362600000000000000