Year thousand metric tons of CO2 equivalent 1990 17.582 1991 17.582 1992 18.327 1993 18.178 1994 17.7608 1995 17.1052 1996 17.284 1997 17.1648 1998 17.1648 1999 17.7906 2000 18.4462 2001 18.4462 2002 18.4462 2003 18.4462 2004 18.4462 2005 18.4462 2006 18.4462 2007 18.6548 2008 19.3104 2009 19.2806 2010 18.6846 2011 18.6548 2012 19.221 2013 19.4594 2014 19.3998 2015 19.6084 2016 19.9958 2017 20.115 2018 19.8468 2019 20.0256 2020 20.0554