Year Number 2004-01-01 30.1712 2005-01-01 35.0697 2006-01-01 40.1846 2007-01-01 46.7889 2008-01-01 50.9513 2009-01-01 51.8641 2010-01-01 50.0390 2011-01-01 50.2633 2012-01-01 54.1301 2013-01-01 52.3916 2014-01-01 54.8083 2015-01-01 54.8532 2016-01-01 62.1718