Year	Number of Firms
1992-01-01	21
1997-01-01	24
2002-01-01	23
2003-01-01	32
2004-01-01	27
2005-01-01	23
2006-01-01	28
2007-01-01	28
2008-01-01	32
2009-01-01	44
2010-01-01	58
2011-01-01	30