Year Percent 1998-01-01 2.35137444492788 1999-01-01 2.27831433142930 2000-01-01 1.87213016869334 2001-01-01 1.84867794348740 2002-01-01 2.40762551416228 2003-01-01 3.15794889278598 2004-01-01 3.33970647467687 2005-01-01 3.81689683615901 2006-01-01 3.76273968448977 2007-01-01 3.79818509402201 2008-01-01 3.72300890100785 2009-01-01 4.99382890725170 2010-01-01 5.49328075863753 2011-01-01 6.95147016877185 2012-01-01 8.66861364121196 2013-01-01 8.77416617244450 2014-01-01 7.33908115459832