Year	Number
2004-01-01	164
2005-01-01	160
2006-01-01	160
2007-01-01	165
2008-01-01	166
2009-01-01	169
2010-01-01	169
2011-01-01	171
2012-01-01	168
2013-01-01	168
2014-01-01	166
2015-01-01	161
2016-01-01	160