Year	current US$
1979	0.017388971554811068
1980	0.06675261277879407
1981	0.47882802728332147
1982	0.5189018816442234
1983	0.6535653788128416
1984	0.7691558174896921
1985	0.8931629623991475
1986	1.0265750659909072
1987	1.2705217442817807
1988	1.7393498680293655
1989	1.8479864121932688
1990	1.7887833045591157
1991	1.6673473643963226
1992	2.5650961052779295
1993	2.7174738491671193
1994	2.6281238922019408
1995	2.8747857220760005
1996	2.1813477083846657
1997	1.675369451557832
1998	1.978267689381892
1999	1.9213959855835432
2000	1.3852032990517922
2001	1.177544548633636
2002	1.1805061071003202
2003	1.0567758839088248
2004	1.3193294764360703
2005	1.3793912541192204
2006	0.9675825079184528
2007	1.3009557053655136
2008	1.3210609186330629
2009	1.1050583620909438
2010	0.5022706909583488
2011	-0.44876898025074663
2012	-0.13331216356589326
2013	-0.4816099790154111
2014	-0.6903547062559
2015	-0.22197180043259607
2016	-0.5702808008962315
2017	-0.7090168795217112
2018	-0.5027731183746685
2019	-0.4323084202677644
2020	-0.4057118559988661
2021	-0.3994307504095542
2022	-0.1999185705200977