Year Percent 1980-01-01 0.051907000000000000 1981-01-01 0.029914000000000000 1982-01-01 0.013065000000000000 1983-01-01 0.013065000000000000 1984-01-01 0.048830000000000000 1985-01-01 0.067923000000000000 1986-01-01 0.064830000000000000 1987-01-01 0.060651000000000000 1988-01-01 0.037368000000000000 1989-01-01 0.034752000000000000 1990-01-01 0.034752000000000000 1991-01-01 0.034752000000000000 1992-01-01 0.034752000000000000 1993-01-01 0.002895000000000000 1994-01-01 0.003062000000000000 1995-01-01 0.002837000000000000 1996-01-01 0.014028000000000000 1997-01-01 0.047662000000000000 1998-01-01 0.044251000000000000 1999-01-01 0.039444000000000000 2000-01-01 0.034266000000000005 2001-01-01 0.031444000000000000 2002-01-01 0.027726000000000000 2003-01-01 0.026344000000000000 2004-01-01 0.029700000000000000 2005-01-01 0.028125000000000000 2006-01-01 0.027908999999999996 2007-01-01 0.027472000000000003 2008-01-01 0.030483999999999997 2009-01-01 0.030840000000000000 2010-01-01 0.029897000000000003 2011-01-01 0.029084000000000000 2012-01-01 0.028275000000000000 2013-01-01 0.027548000000000003 2014-01-01 0.026131000000000000 2015-01-01 0.026699000000000000 2016-01-01 0.025290000000000000