Year	Number of Firms
1992-01-01	1
1997-01-01	2
2002-01-01	2
2003-01-01	1
2004-01-01	4
2005-01-01	3
2006-01-01	3
2007-01-01	4
2008-01-01	4
2009-01-01	2
2010-01-01	5