Year Number of 1990 34528.31 1991 34626.53 1992 34824.01 1993 35207.8 1994 35501.84 1995 35716.13 1996 35326.75 1997 34862.02 1998 35121.78 1999 35665.01 2000 35774.77 2001 35894.27 2002 36133.24 2003 36134.42 2004 35974.3 2005 35957.11 2006 35845.83 2007 36015.43 2008 36349.11 2009 36641.76 2010 37091.07 2011 37503.32 2012 38120.33 2013 38962.07 2014 39719.3 2015 41037.99 2016 42211.47