Year	2011 PPP (% of population)
1984	98.2
1987	98.3
1990	96.8
1993	96.6
1996	94.1
1998	97.9
1999	95.5
2000	95.7
2001	94.8
2002	89.7
2003	88.6
2004	88.6
2005	87.5
2006	89.3
2007	84.7
2008	84.8
2009	83.7
2010	77.8
2011	74.4
2012	73.5
2013	71
2014	69
2015	67
2016	62.4
2017	58.7