Year	current US$
2000	1.49489933
2001	1.38849065
2002	1.68863178
2003	1.49811445
2004	1.55769116
2005	1.57921586
2006	1.88111946
2007	2.94891465
2008	3.41593034
2009	4.02300277
2010	3.74179217
2011	3.54889766
2012	3.35983734
2013	2.67420829
2014	2.91683733
2015	3.87396041
2016	4.26182788
2017	4.81585737
2018	4.73940713
2019	5.09637014
2020	6.72108915
2021	6.56822694