Year	constant 2015 US$
1999	11201.154698286791
2000	11844.1356372035
2001	12511.872744632909
2002	13237.786255550192
2003	13664.470545304155
2004	13983.996348790713
2005	14714.969863108976
2006	14887.582003657402
2007	14448.969420333879
2008	14445.786142352075
2009	15784.246072611975
2010	16129.565758140141
2011	16403.042136526972
2012	15751.684076001402
2013	15421.800762108296
2014	14770.921411794116
2015	15383.190664494361
2016	16206.48156520122
2017	16019.477331405056
2018	16080.445727533173
2019	16646.579131247883
2020	16499.233588787323
2021	15075.74488846493
2022	13576.594382373374