Year	thousand metric tons of CO2 equivalent
1990	396.6
1991	397.2
1992	399
1993	400.4
1994	402.6
1995	404.5
1996	405
1997	462.9
1998	467.5
1999	336.2
2000	373.2
2001	367.5
2002	378.3
2003	397.9
2004	417.7
2005	436.4
2006	458.5
2007	486.1
2008	506.9
2009	529.8
2010	553.9
2011	581.5
2012	593.8
2013	604.4
2014	616.3
2015	684.2
2016	656.3
2017	462.7
2018	504.4
2019	505.2
2020	505.9