Year	2017 PPP (% of population)
1984	39.2
1987	40.1
1989	39.9
1992	37.1
1995	36
1997	27.6
2003	27.8
2006	22.4
2008	22.1
2011	12.9
2013	6.6
2015	4.8
2018	3.4
2021	2.3