Year	2017 PPP (% of population)
1980	20.8
1988	15.2
1989	14.2
1991	13.4
1992	9.6
1996	17.6
1999	21.4
2000	17.5
2001	21
2002	14.2
2003	13
2004	12
2005	10.7
2008	11
2009	9.6
2010	8.3
2011	6.8
2012	6.7
2013	6.1
2014	5.4
2015	4.9
2016	4.9
2017	4.3
2018	4.5
2019	5.3
2020	9.4
2021	7.3
2022	6