Year kt 1960 37696.76 1961 37942.449 1962 41110.737 1963 44913.416 1964 49863.866 1965 52878.14 1966 63149.407 1967 59511.743 1968 69111.949 1969 78019.092 1970 83354.577 1971 76299.269 1972 77421.371 1973 79456.556 1974 72448.919 1975 72173.894 1976 80296.299 1977 79119.192 1978 72687.274 1979 76852.986 1980 64128.496 1981 62808.376 1982 54407.279 1983 49324.817 1984 46394.884 1985 49423.826 1986 48822.438 1987 46849.592 1988 44543.049 1989 42566.536 1990 38375.155 1991 38624.511 1992 38532.836 1993 38532.836 1994 40799.042 1995 41191.411 1996 41283.086 1997 39233.233 1998 40344.334 1999 38899.536 2000 36952.359 2001 37267.721 2002 43208.261 2003 41345.425 2004 39933.63 2005 38378.822 2006 35925.599 2007 34403.794 2008 36490.317 2009 32408.946 2010 38250.477 2011 38554.838 2012 35368.215 2013 32958.996 2014 32412.613 2015 27080.795 2016 32126.587