Year Number of 1990 7672.79 1991 7976.48 1992 8243.11 1993 8557.36 1994 8954.48 1995 9438.11 1996 9764.21 1997 10078.86 1998 10170.05 1999 10403.05 2000 10764.13 2001 10988.97 2002 11296.16 2003 11584.37 2004 11905.27 2005 12327.6 2006 12715.46 2007 13109.07 2008 13540.46 2009 13983.39 2010 14434.48 2011 14672.02 2012 14901.49 2013 15117.45 2014 15250.91 2015 15229.77 2016 15310.87