Year Number of 1990 143.66 1991 154.25 1992 164.9 1993 176.33 1994 188.69 1995 202.02 1996 214.7 1997 226.47 1998 242.59 1999 260.48 2000 277.49 2001 296.31 2002 317.6 2003 338.44 2004 359.79 2005 384.79 2006 406.99 2007 432.7 2008 460.23 2009 493.15 2010 526.4 2011 566.99 2012 606.24 2013 633.7 2014 670.47 2015 712.04 2016 754.2