Year	thousand metric tons of CO2 equivalent
1970	0.7691782
1971	0.7553057
1972	0.750665
1973	0.7584894
1974	0.7549647
1975	0.816013
1976	0.8220022
1977	0.8559131
1978	0.8382524
1979	0.8894365
1980	1.0833787
1981	1.7253081
1982	0.8330971
1983	0.8797676
1984	0.9167072
1985	0.9433889
1986	0.9756599
1987	1.0024842
1988	1.0262674
1989	1.0874149
1990	0.9076583
1991	0.9137157
1992	0.9296745
1993	0.9312803
1994	0.9419877
1995	0.9598344
1996	0.962178
1997	0.9731334
1998	0.9813422
1999	6.954478
2000	20.870533
2001	23.216303
2002	23.21931
2003	23.221139
2004	23.216985
2005	23.216179
2006	23.21714
2007	23.218783
2008	23.220023
2009	23.221418
2010	23.22365
2011	23.4558865
2012	23.688123