Year kt 1960 972030.025 1961 957483.036 1962 953082.636 1963 990090 1964 1021365.843 1965 1057489.46 1966 1094214.465 1967 1103466.306 1968 1092692.66 1969 1108618.441 1970 1181819.095 1971 1206578.679 1972 1243648.382 1973 1257021.931 1974 1260358.901 1975 1298910.072 1976 1334560.646 1977 1356797.334 1978 1349569.677 1979 1352217.251 1980 1425095.209 1981 1293772.605 1982 1312199.28 1983 1304142.881 1984 1297853.976 1985 1478882.765 1986 1520825.911 1987 1525020.959 1988 1543014.928 1989 1466774.331 1990 1235885.343 1991 1102754.908 1992 616584.048 1993 550717.394 1994 517087.337 1995 498000.602 1996 503999.814 1997 453560.229 1998 427652.874 1999 459244.079 2000 464322.874 2001 446673.603 2002 448158.738 2003 449801.554 2004 438092.823 2005 433637.418 2006 449379.849 2007 428719.971 2008 453912.261 2009 368599.506 2010 394580.201 2011 400502.406 2012 456845.861 2013 421646.328 2014 404847.801 2015 453090.853 2016 441708.485