Year Number of 1990 462.61 1991 484.11 1992 502.33 1993 528.58 1994 562.4 1995 647.04 1996 689.9 1997 729.73 1998 774.87 1999 789.41 2000 808.09 2001 819.05 2002 829.3 2003 842.87 2004 840.96 2005 850.27 2006 857.86 2007 869.42 2008 874.92 2009 889.77 2010 896.13 2011 897.04 2012 905.41 2013 915.99 2014 910.48 2015 929.94 2016 952.52