Year Number 2004-01-01 0.9786 2005-01-01 2.6623 2006-01-01 6.2887 2007-01-01 12.0449 2008-01-01 19.1826 2009-01-01 19.6431 2010-01-01 21.5858 2011-01-01 22.5644 2012-01-01 27.8170 2013-01-01 29.7165 2014-01-01 30.9109 2015-01-01 30.4648 2016-01-01 32.2349