Year	Number of Firms
1997-01-01	1
2002-01-01	2
2003-01-01	6
2004-01-01	4
2005-01-01	6
2006-01-01	10
2007-01-01	10
2008-01-01	6
2009-01-01	6
2010-01-01	3
2012-01-01	4