Year	thousand metric tons of CO2 equivalent
1970	2.1193863
1971	2.1645564
1972	2.2963374
1973	2.3779635
1974	2.6683033
1975	2.8820142
1976	3.0883068
1977	3.301066
1978	3.386409
1979	3.40721
1980	3.85454
1981	4.206266
1982	4.350695
1983	5.838323
1984	3.687264
1985	3.42488
1986	3.408047
1987	3.346326
1988	7.038395
1989	6.883798
1990	6.927663
1991	7.453857
1992	7.692154
1993	6.791542
1994	7.976858
1995	8.48625
1996	8.331715
1997	8.118528
1998	10.882674
1999	11.139075
2000	10.172712
2001	10.215306
2002	10.127018
2003	9.963586
2004	11.12497
2005	11.137773
2006	11.412898
2007	11.960389
2008	12.568051
2009	13.117526
2010	13.595081
2011	13.73103181
2012	13.86698262