Year Percent 1998-01-01 0.017942000000000000 1999-01-01 0.015680000000000000 2000-01-01 0.023906999999999998 2001-01-01 0.043967000000000000 2002-01-01 0.036941000000000000 2003-01-01 0.044579000000000000 2004-01-01 0.034190000000000000 2005-01-01 0.028964000000000000 2006-01-01 0.027232000000000000 2007-01-01 0.025091000000000000 2008-01-01 0.021597000000000000 2009-01-01 0.023522000000000000 2010-01-01 0.024595000000000000 2011-01-01 0.023968000000000000 2012-01-01 0.021020000000000000 2013-01-01 0.018528000000000000