Year Percent 1980-01-01 0.1261920000000000 1981-01-01 0.0977730000000000 1982-01-01 0.0977730000000000 1983-01-01 0.0977730000000000 1984-01-01 0.0977730000000000 1985-01-01 0.0977730000000000 1986-01-01 0.0977730000000000 1987-01-01 0.0977730000000000 1988-01-01 0.0977730000000000 1989-01-01 0.0977730000000000 1990-01-01 0.0977730000000000 1991-01-01 0.0977730000000000 1992-01-01 0.0977730000000000 1993-01-01 0.0977730000000000 1994-01-01 0.0977730000000000 1995-01-01 0.0977730000000000 1996-01-01 0.0977730000000000 1997-01-01 0.0977730000000000 1998-01-01 0.0977730000000000 1999-01-01 0.0977730000000000 2000-01-01 0.0977730000000000 2001-01-01 0.0977730000000000 2002-01-01 0.0977730000000000 2003-01-01 0.0977730000000000 2004-01-01 0.0977730000000000 2005-01-01 0.0977730000000000 2006-01-01 0.0977730000000000 2007-01-01 0.3877230000000000 2008-01-01 0.8589170000000000 2009-01-01 3.4466699999999997 2010-01-01 3.4785300000000000 2011-01-01 3.0386400000000000 2012-01-01 2.5755100000000000 2013-01-01 2.0063500000000000 2014-01-01 1.1807200000000000 2015-01-01 1.4497000000000000 2016-01-01 4.3594300000000010