YearPrice
2015$8.43
2014$8.17
2013$8.13
2012$7.96
2011$7.93
2010$7.89
2009$7.50
2008$7.18
2007$6.88
2006$6.55
2005$6.41
2004$6.21
2003$6.03
2002$5.80
2001$5.65
2000$5.39
1999$5.06
1998$4.69
1997$4.59
1996$4.42
1995$4.35
1994$4.08
1993$4.14
1992$4.15
1991$4.21
1990$4.22
1989*$3.99
1988$4.11
1987$3.91
1986$3.71
1985$3.55
1984$3.36
1983$3.15
1982$2.94
1981$2.78
1980$2.69
1979$2.47
1978$2.34
1977$2.23
1976$2.13
1975$2.03
1974$1.89
1971$1.65
1967$1.22
1963$0.86
1958$0.68
1954$0.49
1948$0.36

*1989 and later figures based on NATO survey; previous years based on CPI-W index