Year	2017 PPP (% of population)
1986	16.9
1989	37
1992	23.1
1996	17.6
1997	16.2
2000	16.1
2001	16.1
2002	17.7
2003	21.8
2004	27.9
2005	21.4
2006	18.6
2007	18.1
2008	18.6
2009	16.8
2010	16.7
2011	13.7
2012	14.3
2013	13.7
2014	10.9
2015	8.8
2016	8
2017	5.4
2018	4.2
2019	3.5
2020	5.2
2021	4.3
2022	4