Year	Number
2005-01-01	21797821
2006-01-01	21731836
2007-01-01	21896377
2008-01-01	22017883
2009-01-01	23322071
2010-01-01	23635257
2011-01-01	24385719
2012-01-01	24847084
2013-01-01	22152719
2014-01-01	22677900
2015-01-01	21010838
2016-01-01	18470920