Year	Number
2004-01-01	133
2005-01-01	133
2006-01-01	138
2007-01-01	142
2008-01-01	145
2009-01-01	145
2010-01-01	146
2011-01-01	152
2012-01-01	155
2013-01-01	156
2014-01-01	159
2015-01-01	157
2016-01-01	156