Year Number of Firms 1992-01-01 168 1997-01-01 285 2002-01-01 351 2003-01-01 329 2004-01-01 356 2005-01-01 356 2006-01-01 397 2007-01-01 440 2008-01-01 473 2009-01-01 481 2010-01-01 458 2011-01-01 537 2012-01-01 502 2013-01-01 545 2014-01-01 540 2015-01-01 546 2016-01-01 533