Year	2011 PPP (%)
1981	57.5
1984	59.1
1987	59.1
1990	59.9
1993	60.7
1996	58.6
1999	58.4
2002	57.4
2005	53.6
2008	50.7
2010	49.2
2011	48.3
2012	47.2
2013	46.5
2015	45.4