Year Percent 1997-01-01 0.93120900000000010 1998-01-01 1.26995000000000000 1999-01-01 2.07684000000000020 2000-01-01 1.61887000000000000 2001-01-01 1.95160000000000000 2002-01-01 2.29643000000000000 2003-01-01 1.83259000000000020 2004-01-01 1.54413000000000000 2005-01-01 1.17307000000000000 2006-01-01 0.86322900000000010 2007-01-01 0.64625000000000000 2008-01-01 0.47013000000000000 2009-01-01 0.47237299999999993 2010-01-01 0.30896799999999996 2011-01-01 0.12796200000000000 2012-01-01 0.10672800000000000 2013-01-01 0.09314299999999999 2014-01-01 0.08862300000000001 2015-01-01 0.08801300000000000