Year Number 2004-01-01 2.2213 2005-01-01 2.4388 2006-01-01 2.7022 2007-01-01 3.1932 2008-01-01 3.5731 2009-01-01 4.3587 2010-01-01 5.2629 2011-01-01 6.6415 2012-01-01 8.4412 2013-01-01 13.6572 2014-01-01 10.4136 2015-01-01 14.9994 2016-01-01 13.5890