Year Number 2004-01-01 516.8006 2005-01-01 544.2460 2006-01-01 569.0314 2007-01-01 586.7860 2008-01-01 577.7141 2009-01-01 707.8855 2010-01-01 810.1568 2011-01-01 826.1143 2012-01-01 814.0803 2013-01-01 929.7783 2014-01-01 1234.8512 2015-01-01 1490.6678 2016-01-01 1790.4649 2017-01-01 1843.4447