Year Number of 1990 345.84 1991 357.55 1992 371.72 1993 386.7 1994 400.51 1995 414.26 1996 425.97 1997 431.48 1998 440.79 1999 463.18 2000 480.02 2001 494.12 2002 510.26 2003 528.5 2004 550.65 2005 568.19 2006 589.5 2007 610.23 2008 634.05 2009 657.73 2010 679.95 2011 705.98 2012 720.92 2013 736.38 2014 745.16 2015 741.41 2016 743.01