Year Percent 1999-01-01 3.4349300000000005 2000-01-01 3.2491600000000000 2001-01-01 2.6096100000000000 2002-01-01 0.7944080000000000 2003-01-01 1.1655600000000000 2004-01-01 2.3621400000000000 2005-01-01 3.7250500000000000 2006-01-01 5.1844500000000000 2007-01-01 3.9113599999999997 2008-01-01 2.3637300000000000 2009-01-01 3.5399400000000000 2010-01-01 13.5287000000000000 2011-01-01 9.4598700000000000 2012-01-01 8.5500200000000000 2013-01-01 7.9151300000000000 2014-01-01 10.1640000000000000 2015-01-01 10.1176000000000000 2016-01-01 13.6264000000000000