Year kg per 2015 US$ of GDP 1990 0.5862320883389085 1991 0.5340796732790345 1992 0.5185649015547071 1993 0.4514646295017745 1994 0.3849279928477585 1995 0.3864641386364449 1996 0.38270260489480606 1997 0.35633392603151176 1998 0.3414664748914722 1999 0.3657905691733039 2000 0.33111344926582603 2001 0.37970219763355567 2002 0.3944702324660581 2003 0.4048340849629019 2004 0.36465542824016844 2005 0.37018497916849513 2006 0.3938391439724673 2007 0.3032623537422387 2008 0.29298928113455014 2009 0.3192853376818435 2010 0.33201019090363726 2011 0.33489296980671274 2012 0.30722081499517817 2013 0.29158306940125905 2014 0.28633554510772385 2015 0.2856803857556552 2016 0.2975179199068967 2017 0.30647629048770697 2018 0.3005756562429415 2019 0.2916821286535231 2020 0.370338978678671