Year Number of 1990 182.11 1991 188.17 1992 192.08 1993 197.18 1994 200.05 1995 206.06 1996 209.73 1997 216.63 1998 217.48 1999 219.63 2000 224.59 2001 231.14 2002 239.34 2003 248.43 2004 254.71 2005 260.42 2006 269.61 2007 282.81 2008 297.96 2009 306.58 2010 322.83 2011 330.79 2012 340.24 2013 351.75 2014 361.76 2015 365.3 2016 370.23