Year Percent 1991-01-01 6.596270000000000 1992-01-01 8.103130000000000 1993-01-01 12.716400000000000 1994-01-01 12.981600000000000 1995-01-01 9.289439999999999 1996-01-01 7.289839999999999 1997-01-01 5.398010000000000 1998-01-01 4.754560000000000 1999-01-01 5.287490000000000 2000-01-01 7.106269999999999 2001-01-01 7.145180000000000 2002-01-01 8.834620000000000 2003-01-01 11.564400000000000 2004-01-01 16.173600000000000 2005-01-01 18.047500000000000 2006-01-01 26.326800000000000 2007-01-01 30.986800000000000 2008-01-01 33.272200000000000 2009-01-01 41.499700000000000 2010-01-01 66.930600000000000 2011-01-01 70.291600000000000 2012-01-01 70.378100000000000 2013-01-01 68.949300000000000 2014-01-01 60.769900000000000 2015-01-01 63.966300000000000 2016-01-01 39.259600000000000