Year	Number
2004-01-01	4.8858
2005-01-01	4.8242
2006-01-01	4.7125
2007-01-01	4.6661
2008-01-01	4.5324
2009-01-01	4.4813
2010-01-01	4.3278
2011-01-01	4.4219
2012-01-01	4.3625
2013-01-01	4.2726
2014-01-01	4.2004
2015-01-01	4.1037
2016-01-01	4.0642