Year	2017 PPP (% of population)
1979	9.2
1986	10
1992	4.7
1997	6
2001	4.2
2002	8.5
2003	9
2004	9.7
2005	9.4
2006	9
2007	7.2
2008	7.2
2009	8.2
2010	7.5
2011	7
2012	6.7
2013	5.2
2014	5.5
2015	5
2016	4
2017	4.2
2018	3.2
2019	4
2020	3.2
2021	3.5