Year Number of 1990 2967.6 1991 2975.23 1992 2980.85 1993 3043.47 1994 3101.25 1995 3180.2 1996 3011.06 1997 3046.99 1998 3069.68 1999 3100.42 2000 3129.43 2001 3157.01 2002 3180.52 2003 3202.57 2004 3222.51 2005 3241.16 2006 3247.22 2007 3259.07 2008 3272.06 2009 3290.27 2010 3303.34 2011 3306.14 2012 3318.59 2013 3342.53 2014 3369.44 2015 3405.5 2016 3443.17