Year Percent 1992-01-01 28.729900000000000 1993-01-01 34.394300000000000 1994-01-01 8.984720000000000 1995-01-01 11.808600000000000 1996-01-01 12.682900000000000 1997-01-01 12.724200000000000 1998-01-01 13.496100000000000 1999-01-01 11.995000000000000 2000-01-01 10.249000000000000 2001-01-01 8.846730000000000 2002-01-01 7.897160000000000 2003-01-01 8.156760000000000 2004-01-01 9.444490000000000 2005-01-01 9.815380000000001 2006-01-01 10.404900000000000 2007-01-01 12.761600000000000 2008-01-01 16.557400000000000 2009-01-01 22.080200000000000 2010-01-01 21.307200000000000 2011-01-01 19.508100000000000 2012-01-01 21.575800000000000 2013-01-01 24.593500000000000 2014-01-01 28.842900000000000 2015-01-01 37.704600000000000 2016-01-01 33.960700000000000