Year	2017 PPP (% of population)
1998	56.7
1999	51.1
2000	43.3
2001	28.1
2002	22.3
2003	18.8
2004	10.6
2005	6
2006	3.5
2007	2.7
2008	1.7
2009	1.8
2010	0.9
2011	0.6
2012	0.1
2013	0.1
2014	0.1
2015	0.1
2016	0.1
2017	0.1
2018	0.1
2019	0
2020	0.1