Year	kg per 2021 PPP $ of GDP
2013	0.12760866374933524
2014	0.08578427938710957
2015	0.08858377827096338
2016	0.07323406996320864
2017	0.07083625831309821
2018	0.06953571128595244
2019	0.06800548127204686
2020	0.06703257810453281