Year Number of Firms 1992-01-01 408 1997-01-01 558 2002-01-01 529 2003-01-01 567 2004-01-01 569 2005-01-01 551 2006-01-01 551 2007-01-01 564 2008-01-01 562 2009-01-01 536 2010-01-01 567 2011-01-01 586 2012-01-01 580 2013-01-01 536 2014-01-01 530 2015-01-01 479 2016-01-01 527