Year thousand metric tons of CO2 equivalent 1990 516.5325 1991 573.17 1992 639.49 1993 568.86 1994 579.9925 1995 593.5125 1996 586.1675 1997 526.9625 1998 521.5775 1999 521.9425 2000 460.38 2001 497.0525 2002 362.155 2003 440.155 2004 429.73 2005 384.645 2006 388.8175 2007 368.6525 2008 388.4225 2009 479.765 2010 469.9625 2011 494.315 2012 463.94 2013 485.4375 2014 508.42 2015 487.5775 2016 503.8 2017 484.5175 2018 456.1425 2019 493.79 2020 498.645