Year Number of 1990 93.1 1991 94.13 1992 94.93 1993 95.43 1994 96.47 1995 98.35 1996 99.98 1997 102.4 1998 105.36 1999 108.28 2000 110.94 2001 111.65 2002 112.11 2003 112.83 2004 113.7 2005 114.88 2006 118.05 2007 121.47 2008 125.22 2009 129.18 2010 133.34 2011 135.35 2012 137.42 2013 139.54 2014 141.82 2015 144.32 2016 146.65