pension replacement rate; income substitution rate
Technical term used in pension economics, referring to the ratio of post-retirement income to pre-retirement income provided by the public pension system.
The income substitution rate is one of the indicators showing the benefit level of the public pension.
The government aims to maintain the pension replacement rate at 50% or higher.
Compound of 所得 (income) + 代替 (substitution) + 率 (rate). A modern technical term with no special historical derivation.