Year	Number
2004-01-01	28.3455
2005-01-01	31.1818
2006-01-01	34.2107
2007-01-01	38.1795
2008-01-01	40.6004
2009-01-01	41.9864
2010-01-01	44.1110
2011-01-01	43.7181
2012-01-01	47.4174
2013-01-01	47.2516
2014-01-01	48.8258
2015-01-01	51.0669
2016-01-01	52.6277