Year Number 2004-01-01 3.163107518 2005-01-01 3.300123314 2006-01-01 3.378418055 2007-01-01 3.458670164 2008-01-01 3.552623852 2009-01-01 3.625046488 2010-01-01 3.695511754 2011-01-01 3.793380180 2012-01-01 3.861888078 2013-01-01 3.687682280 2014-01-01 3.812953865