Year Number of 1990 165.52 1991 170.78 1992 176.66 1993 183.38 1994 189.88 1995 196.73 1996 200.43 1997 204.52 1998 208.63 1999 213.45 2000 218.24 2001 225.09 2002 233.79 2003 242.39 2004 252.7 2005 263.04 2006 270.78 2007 280.08 2008 290.37 2009 301.76 2010 313.21 2011 325.96 2012 340.16 2013 355.06 2014 371.26 2015 387.66 2016 402.85