Year	current US$
1993	929.8996173172762
1994	968.4580950819704
1995	1137.844611661119
1996	1277.9037226780954
1997	1336.234080261982
1998	1382.5573613500083
1999	1444.0495140408236
2000	1455.2905903391286
2001	1492.6587251701883
2002	1466.1860765495192
2003	1554.9861928785922
2004	1792.049204207742
2005	2017.5573335692077
2006	2327.465751277722
2007	2855.779728712668
2008	3416.315633872134
2009	3413.9395514190896
2010	3826.3321660721977
2011	3788.7483402081957
2012	4005.6028368440775
2013	3614.70797237342
2014	3524.8118416916286
2015	3199.990721310835
2016	3252.286292365371
2017	3094.894360685111
2018	2786.4756732775127
2019	2800.2743915578476
2020	2604.4890592242386
2021	2903.086614054677