Year Percent 1992-01-01 40.4446000000000000 1993-01-01 19.5320000000000000 1994-01-01 3.0869999999999997 1995-01-01 5.5055900000000000 1996-01-01 5.7765800000000000 1997-01-01 5.3887900000000000 1998-01-01 6.3182199999999990 1999-01-01 8.0508000000000000 2000-01-01 9.0843000000000000 2001-01-01 8.1904600000000000 2002-01-01 6.5723400000000000 2003-01-01 5.5896099999999995 2004-01-01 5.8586500000000000 2005-01-01 6.9155700000000000 2006-01-01 7.7592899999999990 2007-01-01 10.2685000000000000 2008-01-01 15.0404000000000000 2009-01-01 22.0585000000000000 2010-01-01 24.7305000000000000 2011-01-01 29.8894000000000000 2012-01-01 34.2853000000000000 2013-01-01 38.9091000000000000 2014-01-01 42.2983000000000000 2015-01-01 44.4334000000000000 2016-01-01 44.4086000000000000