Year	current US$
2000	23.50893168
2001	21.33172126
2002	23.37801695
2003	28.82873719
2004	32.45263323
2005	33.21493412
2006	34.33262384
2007	38.64980798
2008	42.5709848
2009	41.23498886
2010	39.91930456
2011	42.11430021
2012	42.75302579
2013	44.98648607
2014	45.62607625
2015	40.23952945
2016	40.99428983
2017	43.41971151
2018	43.85427025
2019	42.59520918
2020	41.73744835
2021	44.89312739