Year	Number
2004-01-01	170
2005-01-01	172
2006-01-01	168
2007-01-01	169
2008-01-01	168
2009-01-01	166
2010-01-01	155
2011-01-01	165
2012-01-01	167
2013-01-01	159
2014-01-01	174
2015-01-01	164
2016-01-01	172