Year	Number
2008-01-01	3.3091
2009-01-01	3.3187
2010-01-01	3.2525
2011-01-01	3.5784
2012-01-01	3.1421
2013-01-01	3.6872
2014-01-01	3.8762
2015-01-01	3.7968
2016-01-01	3.8733
2017-01-01	3.5185
