Year	constant 2015 US$
2000	15314668075.702213
2001	15616300569.643656
2002	15968919126.736517
2003	16546882104.888039
2004	16842614019.495907
2005	16999788949.11783
2006	17747789729.640106
2007	18149233277.654205
2008	18705519676.54331
2009	17483022720.539303
2010	18451920971.579575
2011	19136416081.72986
2012	19313252955.193428
2013	19604191696.60677
2014	20067923458.55449
2015	20545471908.577824
2016	21138955591.04915
2017	21955890601.482914
2018	22683263462.470966
2019	23287365721.03883
2020	22428025498.869286
2021	23125499439.062008
2022	23783071536.15488
2023	23521342455.46376