Year Number of 1990 486.41 1991 519.3 1992 553.69 1993 590.1 1994 628.88 1995 670.68 1996 704.71 1997 741.75 1998 781.38 1999 822.87 2000 867.99 2001 909.83 2002 955.1 2003 1003.21 2004 1053.76 2005 1107.97 2006 1179.26 2007 1254.82 2008 1336.15 2009 1423.42 2010 1517.84 2011 1581.2 2012 1645.61 2013 1711.6 2014 1779.2 2015 1848.46 2016 1920.5