Year Number of 1990 324.13 1991 331.61 1992 340.21 1993 350.36 1994 360.28 1995 371.64 1996 382.37 1997 400.65 1998 417.79 1999 435.22 2000 452.26 2001 471.06 2002 490.38 2003 511.13 2004 531.77 2005 552.43 2006 572.74 2007 597.62 2008 622.12 2009 647.01 2010 670.05 2011 692.74 2012 715.88 2013 734.93 2014 756.76 2015 785.48 2016 816.29