Year Number 2004-01-01 138.475096039438 2005-01-01 179.702241321313 2006-01-01 222.806606326032 2007-01-01 261.101265094760 2008-01-01 270.086928072808 2009-01-01 257.803390450118 2010-01-01 263.953227234992 2011-01-01 301.463578144947 2012-01-01 301.137730624549 2013-01-01 335.196326758517 2014-01-01 382.768232324388 2015-01-01 420.480329668105