Year Number of 1990 1257.45 1991 1311.96 1992 1273.81 1993 1253.96 1994 1238.5 1995 1270.04 1996 1244 1997 1211.25 1998 1203.1 1999 1193.04 2000 1176.35 2001 1183.45 2002 1164.83 2003 1167.56 2004 1143.61 2005 1139.09 2006 1132.99 2007 1132.9 2008 1123.51 2009 1122.49 2010 1128.69 2011 1129.43 2012 1125.27 2013 1119.75 2014 1123.26 2015 1131.74 2016 1142.51