Year Number of 1990 318.19 1991 331.13 1992 344.93 1993 359.82 1994 375.71 1995 392.81 1996 411.35 1997 431.11 1998 452.38 1999 474.88 2000 498.72 2001 522.65 2002 547.67 2003 574.6 2004 603.03 2005 633.51 2006 658.24 2007 684.07 2008 712.76 2009 742.8 2010 774.76 2011 801.13 2012 829.81 2013 860.04 2014 891.9 2015 925.43 2016 961.75