Year	constant 2015 US$
1978	36752577.629376404
1979	37169746.88976017
1980	31726879.373572163
1981	35634823.05377614
1982	27328132.990612123
1983	34404699.071510814
1984	29556666.312174585
1985	29235869.788425587
1986	31606317.600413583
1987	30242679.866738953
1988	28766959.04461042
1989	28156591.32381507
1990	31995383.85903641
1991	30688429.189118717
1992	26195604.837685786
1993	24486708.280235104
1994	25910660.727774356
1995	25265592.711386345
1996	27695657.3549626
1997	28964003.927664272
1998	27378003.69308056
1999	30688487.159082346
2000	32856802.924439214
2001	32110548.33655861
2002	32499947.074661516
2003	30587242.617626134
2004	29714207.71931625
2005	32001861.90102313
2006	30288407.4551831
2007	30800456.143807612
2008	32778007.251393497
2009	26335319.696247008
2010	24498852.987612773
2011	25866458.63051679
2012	25516030.200455073
2013	32756833.722182572
2014	29872813.539770994
2015	29408307.467557464
2016	29831024.442248948
2017	37740134.68952922
2018	40873751.79653707
2019	42540504.19043856
2020	36812571.79419257
2021	43363242.89906568
2022	52483309.45506729
2023	54954257.415484086