Year Number of 1990 541.49 1991 554.05 1992 569.52 1993 590.72 1994 611.18 1995 628.61 1996 653.37 1997 676.73 1998 696.5 1999 718.05 2000 737.9 2001 769.42 2002 798.21 2003 829.17 2004 861.42 2005 898.22 2006 934.14 2007 969.94 2008 1015.49 2009 1066.39 2010 1120.01 2011 1144.72 2012 1181.49 2013 1203.96 2014 1241.89 2015 1282.09 2016 1318.94