Year	2017 PPP (% of population)
1987	17.6
1994	17.1
1995	13.8
1998	15.7
1999	21.8
2000	28.2
2003	14.8
2004	15.1
2005	11.8
2006	8.2
2007	8.5
2008	7.5
2009	7.3
2010	5.7
2011	4.7
2012	4.5
2013	3.2
2014	2.6
2015	3.4
2016	3.6
2017	3.2
2018	3.3
2019	3.6
2020	6.5
2021	3.6
2022	3.2