noun
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.
所得代替率は、公的年金の給付水準を示す指標の一つです。
The income substitution rate is one of the indicators showing the benefit level of the public pension.
政府は所得代替率を50%以上に維持することを目標としている。
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.