Year	2011 PPP (%)
1981	31.3
1984	28.8
1987	26.5
1990	26.7
1993	25.7
1996	22.9
1999	22.3
2002	20.1
2005	16.9
2008	15
2010	13.4
2011	12
2012	11.4
2013	10.2
2015	9.2