Year Number 2004-01-01 33.40254347 2005-01-01 48.65849954 2006-01-01 63.24249979 2007-01-01 40.97497228 2008-01-01 55.15724144 2009-01-01 74.72470661 2010-01-01 73.04000808 2011-01-01 16.99874835 2012-01-01 75.29483417 2013-01-01 54.25876915 2014-01-01 60.15615419