Year Number of 1990 401.82 1991 420.56 1992 441.12 1993 462.14 1994 480.49 1995 495.23 1996 507.57 1997 526.29 1998 537.51 1999 558.31 2000 574.41 2001 590.74 2002 617.07 2003 637.66 2004 658.84 2005 681.51 2006 701.7 2007 722.66 2008 744.07 2009 766.58 2010 790.96 2011 813.24 2012 838.72 2013 863.47 2014 889.28 2015 916.26 2016 941.9