Year Tonnes 1945 3667 1946 95481346 1947 187644057 1948 288163861 1949 405449189 1950 569019391 1951 748225681 1952 937769244 1953 1147719662 1954 1368561070 1955 1606556704 1956 1850599221 1957 2102621130 1958 2359281794 1959 2618296672 1960 2889001946 1961 3173682157 1962 3471889931 1963 3778744491 1964 4095037909 1965 4405464127 1966 4717672507 1967 5021307441 1968 5329001744 1969 5650626980 1970 5930503421 1971 6215399985 1972 6497861661 1973 6784434044 1974 7071439133 1975 7360197048 1976 7656211956 1977 7960107247 1978 8266998477 1979 8579184855 1980 8895470939 1981 9212739779 1982 9530962039 1983 9847255457 1984 10173284760 1985 10515144502 1986 10860451224 1987 11205405914 1988 11543019270 1989 11877082970 1990 12187153489