Year	Number
2004-01-01	12.4990
2005-01-01	15.9458
2006-01-01	17.9781
2007-01-01	18.5601
2008-01-01	19.0707
2009-01-01	21.8603
2010-01-01	29.5389
2011-01-01	33.5894
2012-01-01	35.4955
2013-01-01	28.1564
2014-01-01	32.4106
2015-01-01	32.4834