Year Number of 1990 36725.74 1991 37744.3 1992 38923.35 1993 40149.4 1994 41066.83 1995 42077.62 1996 42887.52 1997 43980.53 1998 45089.14 1999 46430.36 2000 47991.41 2001 49868.67 2002 51430.66 2003 51560.59 2004 51975.12 2005 53183.18 2006 54009.77 2007 55056.66 2008 56247.68 2009 57184.7 2010 57987.49 2011 58606.22 2012 59567.79 2013 60339.2 2014 62059.04 2015 62413.39 2016 62862.57