Year Number of 1990 668.2 1991 673.01 1992 681.5 1993 690.8 1994 702.95 1995 715.88 1996 729.1 1997 717.91 1998 707.49 1999 694.35 2000 686.17 2001 664.88 2002 655.58 2003 656.38 2004 665.08 2005 672.5 2006 675.28 2007 675.84 2008 685.56 2009 700.91 2010 726.24 2011 749.09 2012 770.75 2013 791.42 2014 813.99 2015 836.77 2016 860.95