Year	Number of Firms
1997-01-01	2
2003-01-01	2
2004-01-01	3
2005-01-01	3
2006-01-01	1
2007-01-01	2
2008-01-01	2
2009-01-01	3
2010-01-01	3
2011-01-01	3
2012-01-01	6
2013-01-01	5
2014-01-01	3
2015-01-01	4
2016-01-01	1