Year Percent 1982-01-01 87.7018000000000000 1983-01-01 86.4008000000000000 1984-01-01 82.0752000000000000 1985-01-01 78.8812000000000000 1986-01-01 79.4615000000000000 1987-01-01 64.4747000000000000 1988-01-01 46.9522000000000000 1989-01-01 42.5482000000000000 1990-01-01 50.3133000000000000 1991-01-01 60.4094000000000000 1992-01-01 58.7074000000000000 1993-01-01 55.8457000000000000 1994-01-01 52.4869999999999950 1995-01-01 50.5693000000000000 1996-01-01 44.2857000000000000 1997-01-01 33.6333000000000000 1998-01-01 28.4118000000000000 1999-01-01 23.8274000000000000 2000-01-01 17.8516000000000000 2001-01-01 12.8408000000000000 2002-01-01 8.3963399999999990 2003-01-01 5.3938200000000000 2004-01-01 3.3012599999999996 2005-01-01 1.7981099999999999 2006-01-01 1.0414200000000000 2007-01-01 0.7995110000000000 2008-01-01 0.9818979999999999 2009-01-01 1.2682600000000000 2010-01-01 1.0176800000000000 2011-01-01 0.7797260000000000 2012-01-01 0.5838310000000000 2013-01-01 0.4998030000000000 2014-01-01 0.4686530000000000 2015-01-01 0.3044150000000000 2016-01-01 0.1326170000000000