Year	Number of Firms
1997-01-01	4
2002-01-01	12
2003-01-01	19
2004-01-01	28
2005-01-01	21
2006-01-01	17
2007-01-01	23
2008-01-01	27
2009-01-01	17
2010-01-01	21
2011-01-01	22
2012-01-01	14
2013-01-01	21
2014-01-01	22
2015-01-01	20
2016-01-01	15