Year	2011 PPP (%)
1981	55.5
1984	57.1
1987	56.9
1990	57.8
1993	61.1
1996	59.5
1999	56.3
2002	55
2005	52.6
2008	49.2
2010	46.9
2011	46.6
2012	45.4
2013	44.7
2015	44.6