Year thousand metric tons of CO2 equivalent 1990 14.2 1991 15.1 1992 16.4 1993 17.1 1994 18.1 1995 19.3 1996 20.6 1997 21.7 1998 20.1 1999 19.8 2000 19.7 2001 20.2 2002 21 2003 22.1 2004 22.9 2005 22.3 2006 25 2007 26.7 2008 27.6 2009 27.9 2010 28.4 2011 30.4 2012 31.9 2013 31.6 2014 32.2 2015 32 2016 32 2017 32.1 2018 32.8 2019 34.5 2020 41.3