Year	2011 PPP (% of population)
1997	43.3
1998	57.1
1999	69.5
2000	68.4
2001	59.6
2002	44
2003	32
2004	32.5
2005	40.3
2006	12.6
2007	7.8
2008	9.1
2009	8.1
2010	6
2011	4.3
2012	3.4
2013	2.2
2014	1.1
2015	1.4
2016	1.3
2017	1.1