Year Number of 1990 113.01 1991 118.21 1992 123.92 1993 130.09 1994 136.67 1995 143.82 1996 148.93 1997 154.49 1998 160.43 1999 166.62 2000 173.27 2001 175.87 2002 178.72 2003 181.73 2004 184.87 2005 188.42 2006 190.45 2007 192.54 2008 195.26 2009 198.25 2010 201.75 2011 204.78 2012 208.51 2013 212.6 2014 217 2015 221.69 2016 226.69