Year	2011 PPP (% of population)
1992	22.6
1996	32.1
1999	36
2000	30.7
2001	36.6
2002	30.3
2003	27.2
2004	26.5
2005	23.4
2008	22.4
2009	20.5
2010	18.3
2011	16.3
2012	15.4
2013	14.2
2014	13.1
2015	11.9
2016	11.8
2017	10.8