Year Number of 1990 5825.83 1991 5913.7 1992 6345.49 1993 6568.51 1994 6853.97 1995 7175.51 1996 7258.08 1997 7270.49 1998 7031.8 1999 6771.66 2000 6826.41 2001 7119.9 2002 7256.36 2003 7317.68 2004 7296.59 2005 7351.7 2006 7413.81 2007 7575.11 2008 8039.8 2009 8226.3 2010 8361.04 2011 7910.21 2012 8007.95 2013 8003.19 2014 8214.29 2015 8112.35 2016 8057.88