Year Number 2004-01-01 7.3953 2005-01-01 8.6888 2006-01-01 10.4363 2007-01-01 23.7076 2008-01-01 188.5361 2009-01-01 217.0005 2010-01-01 267.6308 2011-01-01 290.3070 2012-01-01 332.6096 2013-01-01 303.4812 2014-01-01 242.7873 2015-01-01 198.8275 2016-01-01 235.4251 2017-01-01 241.5855