Year thousand metric tons of CO2 equivalent 1969 0 1970 0.70631578 1971 0.70167353 1972 0.70437208 1973 0.70066231 1974 0.69987522 1975 0.70420127 1976 0.70277062 1977 0.70969199 1978 0.70667104 1979 0.70932929 1980 0.69989537 1981 0.69801708 1982 0.69669245 1983 0.70164811 1984 0.69989165 1985 0.69336336 1986 0.69526087 1987 0.70535664 1988 0.7204431 1989 0.71577202 1990 0.70712984 1991 0.70335156 1992 0.70445392 1993 0.70365412 1994 0.71696087 1995 0.71986805 1996 0.71566259 1997 0.72680647 1998 0.73727858 1999 0.73683528 2000 0.74674908 2001 0.75058099 2002 0.75633366 2003 0.7704027 2004 0.76702339 2005 0.76702339 2006 0.76702339 2007 0.76702339 2008 0.76702339