Year Number of 1990 1955.72 1991 1973.39 1992 1984.08 1993 1990.99 1994 1992.38 1995 1989.75 1996 1973.64 1997 1964.04 1998 1955.75 1999 1949 2000 1939.06 2001 1921.09 2002 1905.56 2003 1883.07 2004 1860.32 2005 1833.6 2006 1803.58 2007 1777.08 2008 1763.04 2009 1758.57 2010 1757.68 2011 1752.9 2012 1750.93 2013 1755.98 2014 1766.03 2015 1782.37 2016 1803.91