Year	constant 2015 US$
1991	4771.417687683969
1992	4898.438698590611
1993	5006.218310322237
1994	4862.745508340616
1995	4677.862995160888
1996	4696.598463954614
1997	4647.80843037356
1998	4693.305658368787
1999	4814.717631393144
2000	4739.63754024352
2001	4759.995892734638
2002	4760.139081968058
2003	4444.502043196848
2004	5161.158024892043
2005	5320.544251520309
2006	5358.54154203106
2007	5564.829682020947
2008	5914.249739904542
2009	6065.03580518769
2010	6315.864517080051
2011	6319.461453965822
2012	6326.12771107477
2013	6601.558645060704
2014	6647.525329542495
2015	6549.7369637157235
2016	6390.9247595468005
2017	6295.279288161621
2018	6283.712468979959
2019	6222.992137749148
2020	6054.739950686237
2021	6135.306436606395
2022	6123.005114863631