Year Number 2004-01-01 1.3811 2005-01-01 1.4643 2006-01-01 1.5880 2007-01-01 1.8353 2008-01-01 2.4623 2009-01-01 2.7342 2010-01-01 4.3296 2011-01-01 4.3497 2012-01-01 4.5664 2013-01-01 4.4916 2014-01-01 4.6652 2015-01-01 4.9545 2016-01-01 5.0929