Year Number 2004-01-01 30.2462 2005-01-01 29.5765 2006-01-01 30.5122 2007-01-01 33.0102 2008-01-01 32.2482 2009-01-01 30.0067 2010-01-01 44.4954 2011-01-01 45.9678 2012-01-01 46.7536 2013-01-01 46.1348 2014-01-01 44.8453 2015-01-01 44.2982 2016-01-01 37.5979 2017-01-01 43.8642