Year Number of 1990 35963.85 1991 36209.34 1992 36596.12 1993 36698.89 1994 36745.41 1995 36925.67 1996 36941.01 1997 36695.45 1998 36523.8 1999 36366.6 2000 36071.3 2001 35635.9 2002 35489.79 2003 35464.73 2004 35461.86 2005 35658.4 2006 35858.12 2007 36165.45 2008 36523.89 2009 36815.82 2010 37127.04 2011 37680.88 2012 38399.17 2013 39145.58 2014 39584.2 2015 40287.78 2016 41104.25