Circular 02/2009/TT-BLDTBXH, issued by the Ministry of Labour, Invalids and Social Affairs on 15 January 2009, guides how to index (adjust) the monthly income on which voluntary social insurance contributions were paid, implementing Government Decree 134/2008/ND-CP. It applies to people who joined voluntary social insurance from 1 January 2008 onward and later draw a pension, a lump-sum allowance on retirement, a one-time social insurance benefit, or whose survivors receive a one-time death benefit. Two cases are covered: those with no prior compulsory social insurance, and those who previously paid compulsory social insurance. The adjustment restates past contribution income into comparable present terms using the average annual consumer price index defined in Decree 134/2008/ND-CP. For voluntary-insurance periods, the indexed monthly…