Year	current US$
2000	4.69348836
2001	4.00555184
2002	9.56634818
2003	13.87466267
2004	7.95683578
2005	12.38252655
2006	14.7235482
2007	14.69909407
2008	11.69392493
2009	11.72254849
2010	9.84252556
2011	7.07160857
2012	12.14520363
2013	8.03603404
2014	11.0166808
2015	23.24479723
2016	18.820543
2017	16.95163582
2018	12.74836723
2019	11.62994131
2020	13.64555619
2021	39.41124676