Year Number of Firms 1992-01-01 1 1997-01-01 1 2002-01-01 1 2005-01-01 1 2006-01-01 3 2008-01-01 2 2009-01-01 2 2010-01-01 3 2011-01-01 4 2012-01-01 7 2013-01-01 2 2014-01-01 5 2015-01-01 4 2016-01-01 2