Year	2017 PPP (% of population)
1983	3
1987	0.7
1990	1.7
1993	3
1999	0.7
2004	0.8
2005	0.5
2006	0.2
2007	0.4
2008	0.6
2009	0.4
2010	0.2
2011	0.4
2012	0.2
2013	0.3
2014	0.4
2015	0.4
2016	0.4
2017	0.4
2018	0.4
2019	0.4
2020	0.2
2021	0.3