Year	Number of Firms
1997-01-01	1
2002-01-01	3
2003-01-01	1
2004-01-01	3
2006-01-01	2
2007-01-01	4
2008-01-01	2
2010-01-01	1
2013-01-01	2
2014-01-01	3
2015-01-01	2
2016-01-01	6