Date Value Value
Dec 31, 2014 30,176
Dec 31, 2013 30,518
Dec 31, 2012 29,161
Dec 31, 2011 29,005
Dec 31, 2010 28,838
Dec 31, 2009 29,274
Dec 31, 2008 29,649
Dec 31, 2007 30,605
Dec 31, 2006 30,943
Dec 31, 2005 30,350
Dec 31, 2004 29,901
Dec 31, 2003 29,961
Dec 31, 2002 29,995
Dec 31, 2001 30,556
Dec 31, 2000 30,719
Dec 31, 1999 30,188
Dec 31, 1998 29,206
Dec 31, 1997 28,308
Dec 31, 1996 27,259
Dec 31, 1995 26,594
Dec 31, 1994 26,172
Dec 31, 1993 25,463
Dec 31, 1992 24,554
Dec 31, 1991 24,787
Dec 31, 1990 25,284
Dec 31, 1989 25,921
Dec 31, 1988 25,244
Dec 31, 1987 24,711
Dec 31, 1986 24,059
Dec 31, 1985 23,116
Dec 31, 1984 22,422
Dec 31, 1983 21,470
Dec 31, 1982 21,160
Dec 31, 1981 21,178
Dec 31, 1980 21,309
Dec 31, 1979 21,811
Dec 31, 1978 21,504
Dec 31, 1977 20,594
Dec 31, 1976 19,948
Dec 31, 1975 19,283
Dec 31, 1974 19,252
Dec 31, 1973 19,729
Dec 31, 1972 19,081
Dec 31, 1971 17,818
Dec 31, 1970 17,292
Dec 31, 1969 17,173
Dec 31, 1968 16,292
Dec 31, 1967 15,276