Year	2017 PPP (%)
1977	22
1983	18
1987	14.6
1993	12.9
2004	10
2009	7.6
2011	4.7
2015	3.8
2016	3.6
2017	2.5
2018	2.2
2019	2.8
2020	3.4
2021	2.7