Year Number of 1990 13172.04 1991 13280.3 1992 13403.1 1993 13618.51 1994 13791.94 1995 13760.11 1996 13872.43 1997 13849.57 1998 13894.15 1999 13976.69 2000 14132.1 2001 14194.6 2002 14309.38 2003 14338.1 2004 14327 2005 14408.13 2006 14463.02 2007 14515.08 2008 14611.38 2009 14712.49 2010 14812.93 2011 14963.12 2012 15134.94 2013 15299.09 2014 15328.77 2015 15717.15 2016 16120.88