Year	current US$
2000	10.487486968249316
2001	9.786446906550204
2002	9.123303064346551
2003	14.235720188986035
2004	17.704530745483073
2005	19.984048921886696
2006	23.11420723378913
2007	25.921269311953072
2008	26.877043681613387
2009	27.987832776193653
2010	32.31064765275977
2011	35.46841275978855
2012	34.992609659274784
2013	33.597329196783456
2014	33.143484006180564
2015	30.475079175128695
2016	28.161888288676096
2017	30.665139187083376
2018	31.356710827056023
2019	31.180199222228985
2020	30.683593864045406
2021	34.00822172686666