Year thousand metric tons of CO2 equivalent 1990 21571.5 1991 22761.9 1992 21164.1 1993 22799.7 1994 26471.5 1995 27120.2 1996 27811.6 1997 28571.2 1998 30007.1 1999 30127.5 2000 30203.8 2001 30812.8 2002 32482.1 2003 32140.4 2004 32651 2005 30037.4 2006 31468.7 2007 30155.5 2008 31695.9 2009 29152.3 2010 28778.4 2011 27831.7 2012 26342.6 2013 24981.2 2014 22658.5 2015 22005.8 2016 22508 2017 22601.5 2018 26169.8 2019 25939 2020 24772.9