Year	current US$
2000	3.23292445
2001	4.97187591
2002	3.85358864
2003	7.18994278
2004	11.45676995
2005	13.78175025
2006	13.92146081
2007	13.77025835
2008	14.31725216
2009	10.8275485
2010	10.28339128
2011	11.99699252
2012	14.75375525
2013	14.42034853
2014	14.13274184
2015	15.83450613
2016	10.18705905
2017	10.34366801
2018	10.57700393
2019	10.96531682
2020	10.44123687
2021	11.12788484