Year Number of 1990 540.09 1991 549.09 1992 552.82 1993 576.57 1994 584.34 1995 588.47 1996 586.24 1997 578.17 1998 586.35 1999 611.5 2000 613.1 2001 627.24 2002 638.23 2003 645.37 2004 659.98 2005 671 2006 680.97 2007 689.77 2008 697.78 2009 705.13 2010 712.1 2011 719.58 2012 728.08 2013 736.86 2014 744.39 2015 752.51 2016 757.43