Year	Number of Firms
1992-01-01	1
2002-01-01	4
2003-01-01	3
2004-01-01	4
2006-01-01	3
2007-01-01	2
2009-01-01	1
2010-01-01	4
2012-01-01	1
2013-01-01	2
2014-01-01	1
2015-01-01	1