Year Number of Firms 1992-01-01 4 1997-01-01 1 2002-01-01 2 2003-01-01 2 2004-01-01 2 2005-01-01 3 2006-01-01 3 2007-01-01 2 2008-01-01 6 2009-01-01 3 2010-01-01 3 2011-01-01 3 2012-01-01 3 2013-01-01 6 2014-01-01 2 2015-01-01 4 2016-01-01 2