Year	2017 PPP (% of population)
1997	61.3
1998	62.3
1999	62.1
2000	62.4
2001	63.9
2002	60.2
2003	59.4
2004	59.8
2005	61.5
2006	55.9
2007	50.3
2008	46.4
2009	44.6
2010	40.5
2011	38.1
2012	35.3
2013	34.5
2014	33.4
2015	32.7
2016	31.8
2017	32.6
2018	30.3
2019	28.8
2020	42.8
2021	33.4
2022	32.2