Year	Number
2004-01-01	13196289
2005-01-01	13696960
2006-01-01	14397699
2007-01-01	16906570
2008-01-01	19144947
2009-01-01	20612316
2010-01-01	22778928
2011-01-01	24222013
2012-01-01	28199995
2013-01-01	29030830
2014-01-01	29276450
2015-01-01	29172959
2016-01-01	31223929
2017-01-01	32035694