{"Year":1959,"Average":315.98}
{"Year":1960,"Average":316.91}
{"Year":1961,"Average":317.64}
{"Year":1962,"Average":318.45}
{"Year":1963,"Average":318.99}
{"Year":1965,"Average":320.04}
{"Year":1966,"Average":321.38}
{"Year":1967,"Average":322.16}
{"Year":1968,"Average":323.05}
{"Year":1969,"Average":324.63}
{"Year":1970,"Average":325.68}
{"Year":1971,"Average":326.32}
{"Year":1972,"Average":327.45}
{"Year":1973,"Average":329.68}
{"Year":1974,"Average":330.25}
{"Year":1975,"Average":331.15}
{"Year":1976,"Average":332.15}
{"Year":1977,"Average":333.9}
{"Year":1978,"Average":335.51}
{"Year":1979,"Average":336.85}
{"Year":1980,"Average":338.69}
{"Year":1981,"Average":339.93}
{"Year":1982,"Average":341.13}
{"Year":1983,"Average":342.78}
{"Year":1984,"Average":344.42}
{"Year":1985,"Average":345.9}
{"Year":1986,"Average":347.15}
{"Year":1987,"Average":348.93}
{"Year":1988,"Average":351.48}
{"Year":1989,"Average":352.91}
{"Year":1990,"Average":354.19}
{"Year":1991,"Average":355.59}
{"Year":1992,"Average":356.37}
{"Year":1993,"Average":357.04}
{"Year":1994,"Average":358.89}
{"Year":1995,"Average":360.88}
{"Year":1996,"Average":362.64}
{"Year":1997,"Average":363.76}
{"Year":1998,"Average":366.63}
{"Year":1999,"Average":368.31}
{"Year":2000,"Average":369.48}
{"Year":2001,"Average":371.02}
{"Year":2002,"Average":373.1}
{"Year":2003,"Average":375.64}
{"Year":2004,"Average":377.38}
{"Year":2005,"Average":379.67}
{"Year":2006,"Average":381.84}
{"Year":2007,"Average":383.55}
{"Year":2008,"Average":385.34}