Year Percent 1980-01-01 0.413555000000000000 1981-01-01 0.401316000000000000 1982-01-01 0.396684000000000040 1983-01-01 0.421010000000000050 1984-01-01 0.431727000000000000 1985-01-01 0.356056000000000000 1986-01-01 0.468809000000000030 1987-01-01 0.490450000000000000 1988-01-01 0.061025000000000000 1989-01-01 0.070807000000000010 1990-01-01 0.069258000000000000 1991-01-01 0.061611000000000000 1992-01-01 0.054373000000000005 1993-01-01 0.128797000000000000 1994-01-01 1.101860000000000000 1995-01-01 24.179600000000000000 1996-01-01 23.610100000000000000 1997-01-01 22.831500000000000000 1998-01-01 19.916500000000000000 1999-01-01 26.167800000000000000 2000-01-01 46.038999999999994000 2001-01-01 24.808300000000000000 2002-01-01 21.359700000000000000 2003-01-01 19.126200000000000000 2004-01-01 17.082900000000000000 2005-01-01 16.750000000000000000 2006-01-01 13.488700000000000000 2007-01-01 12.251100000000000000 2008-01-01 10.077800000000000000 2009-01-01 5.199540000000000000 2010-01-01 4.212810000000000000 2011-01-01 2.861430000000000000 2012-01-01 2.322580000000000000 2013-01-01 1.544379999999999900 2014-01-01 2.808300000000000000 2015-01-01 3.710709999999999700 2016-01-01 6.629950000000000000