The amount specified by Cabinet Order as referred to in Article 165, paragraph (2) of the Act is the amount obtained by deducting, from the total sum of the premiums for each month of the period covered by advance payment, the total sum of the amounts obtained by discounting the amount of the premium for each month of that period by the compound present value method at an annual interest rate of 4%, according to the respective periods from the first month of the period covered by the advance payment to each such month (where that total has a fractional amount of less than one yen, a fractional amount of less than 50 sen is rounded down, and a fractional amount of 50 sen or more is calculated as one yen).
法第百六十五条第二項の政令で定める額は、前納に係る期間の各月の保険料の合計額から、その期間の各月の保険料の額を年四分の利率による複利現価法によって前納に係る期間の最初の月から当該各月までのそれぞれの期間に応じて割り引いた額の合計額（この額に一円未満の端数がある場合において、その端数金額が五十銭未満であるときは、これを切り捨て、その端数金額が五十銭以上であるときは、これを一円として計算する。）を控除した額とする。
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