Year	Number
2004-01-01	1.9193
2005-01-01	2.2523
2006-01-01	2.5852
2007-01-01	3.4861
2008-01-01	3.7799
2009-01-01	3.8386
2010-01-01	3.8778
2011-01-01	4.0149
2012-01-01	4.1520
2013-01-01	4.2107
2014-01-01	4.4262
2015-01-01	4.4653
2016-01-01	4.5437
2017-01-01	4.7787