Year	2017 PPP (% of population)
1987	59.6
1994	64.8
1995	64.4
1998	64.3
1999	67.8
2000	75.9
2003	57.7
2004	59
2005	50.6
2006	45.8
2007	44.9
2008	42.3
2009	43.2
2010	38.8
2011	34.7
2012	31.4
2013	31.2
2014	27.6
2015	28.8
2016	28.2
2017	27.1
2018	27.8
2019	29.7
2020	34.6
2021	31.7
2022	29.9