Year Number 2004-01-01 14.0266 2005-01-01 15.1442 2006-01-01 16.1640 2007-01-01 16.7215 2008-01-01 19.0943 2009-01-01 5.3579 2010-01-01 4.7479 2011-01-01 5.2492 2012-01-01 5.4171 2013-01-01 6.3835 2014-01-01 7.1955 2015-01-01 7.4424 2016-01-01 8.2219 2017-01-01 9.2500