Year	Number of Firms
1992-01-01	226
1997-01-01	194
2002-01-01	284
2003-01-01	277
2004-01-01	345
2005-01-01	332
2006-01-01	335
2007-01-01	372
2008-01-01	388
2009-01-01	423
2010-01-01	461
2011-01-01	282