Year Number 2005-01-01 273.3118 2006-01-01 315.8487 2007-01-01 366.2671 2008-01-01 441.4098 2009-01-01 504.3927 2010-01-01 518.8238 2011-01-01 520.3427 2012-01-01 532.9533 2013-01-01 487.8455 2014-01-01 441.3226 2015-01-01 426.3703 2016-01-01 415.3848 2017-01-01 441.0106