Year	base year varies by country
1960	2.55917797413422
1961	2.833698425730461
1962	2.7830195996742555
1963	2.8987007763915855
1964	3.291347533256067
1965	3.7820929327867887
1966	3.6511815366178637
1967	3.647761107255465
1968	3.7965900084155337
1969	4.064094769983608
1970	4.020954461234578
1971	3.9647084618349226
1972	4.963923488456266
1973	5.570356855529246
1974	6.632937180936397
1975	7.103376525390619
1976	8.151383009785913
1977	8.91575748129527
1978	10.165609526219853
1979	12.304463015637348
1980	25.554614221123977
1981	28.654507330918893
1982	34.576478782345056
1983	45.95831414285711
1984	78.6496123097428
1985	79.98069210580503
1986	120.48150826435258
1987	167.2197813510803
1988	295.614269780862
1989	611.5029166188705