Year Number of 1990 607.09 1991 627.94 1992 653.5 1993 676.06 1994 692.3 1995 720.08 1996 750.52 1997 762.27 1998 778.93 1999 783.8 2000 787.07 2001 797.35 2002 808.43 2003 810.52 2004 823.57 2005 821.88 2006 836.44 2007 837.65 2008 845.59 2009 859.67 2010 879.9 2011 898.43 2012 914.44 2013 928.48 2014 943.65 2015 971.97 2016 997.32