Year	kg per 2015 US$ of GDP
1990	0.3773792507458056
1991	0.36507609338940067
1992	0.3446634380853158
1993	0.3254151605115836
1994	0.31208137192656077
1995	0.32402453590656277
1996	0.33332784153619194
1997	0.31730887366168575
1998	0.3214162907991654
1999	0.3372731133544328
2000	0.3343025779532345
2001	0.33118539699078375
2002	0.34855281122226767
2003	0.34803813324665916
2004	0.3535303555338196
2005	0.33539293309284035
2006	0.32938354039299517
2007	0.31757968718282265
2008	0.3134664194886843
2009	0.3119389878849577
2010	0.3025416219764526
2011	0.30147512537264387
2012	0.30686696924573803
2013	0.30858454683197667
2014	0.31022463867533356
2015	0.31198019829664175
2016	0.3145021891169292
2017	0.29938216281597857
2018	0.30335980626157094
2019	0.294272085143803
2020	0.30014294141953485