Supplementary Provisions, Article 8, paragraph (6)
第六項
The number of months referred to in paragraph (3), item (i) is calculated in accordance with the calendar, and any fraction of less than one month is rounded down.
第三項第一号の月数は、暦に従って計算し、一月に満たない端数を生じたときは、これを切り捨てる。