Year thousand metric tons of CO2 equivalent 1990 8794.8 1991 1404.8 1992 7864.7 1993 14346.2 1994 15944.2 1995 15987.5 1996 16183.3 1997 16724.3 1998 16270.6 1999 15004.1 2000 16324.2 2001 15906.2 2002 15023.4 2003 17518.5 2004 18770.7 2005 19717.8 2006 20224.9 2007 19482.4 2008 20437.2 2009 18122.6 2010 18624 2011 20441.3 2012 21634.6 2013 22535.7 2014 22244.7 2015 21986.9 2016 23477.3 2017 21822.4 2018 22088.2 2019 21796.8 2020 20085.2