Year kg per 2015 US$ of GDP 2000 0.1737068771821037 2001 0.19366828118374554 2002 0.19408903166387884 2003 0.21013749586663694 2004 0.16197336171964816 2005 0.22105080599270868 2006 0.24424589081043013 2007 0.26758411890080147 2008 0.3956133532514081 2009 0.4885175843466518 2010 0.55853900427753 2011 0.7757347439784814 2012 0.5871299991814509 2013 0.5120868865905596 2014 0.4921047546618268 2015 0.5256336101222481 2016 0.4750378342642521 2017 0.4990269494908474 2018 0.5398863644988409 2019 0.5321800314930399 2020 0.4223396425043372