Year Number of 1990 86.39 1991 88.66 1992 91.1 1993 93.72 1994 96.55 1995 99.73 1996 103.3 1997 107.29 1998 111.59 1999 116.04 2000 120.67 2001 125.09 2002 129.68 2003 134.54 2004 139.63 2005 145.1 2006 149.81 2007 154.68 2008 159.98 2009 165.82 2010 172.38 2011 178.49 2012 185.4 2013 192.73 2014 200.58 2015 208.84 2016 216.31