Year Number of 1990 64.98 1991 64.9 1992 65.79 1993 66.8 1994 67.92 1995 69.55 1996 72.13 1997 73.56 1998 78.01 1999 82.22 2000 86.36 2001 87.5 2002 89.86 2003 95.05 2004 101.55 2005 108.41 2006 116.51 2007 123.65 2008 129.98 2009 136.6 2010 142.45 2011 148.84 2012 159.1 2013 169.6 2014 180.88 2015 191.86 2016 202.24