in countries where the lunisolar calendar is still used or when counting the age of the deceased who lived during the period when the lunisolar calendar (the old lunisolar calendar ) was used , age is counted with the new year ' s day as the base date of the calendar used in the relevant country back in these days . 現在も太陰太陽暦を用いている国や、太陰太陽暦（旧暦）を用いていた時代の物故者については、その国の当時の暦法の元日を基準として加算される。
the day used as the base date for counting anniversaries in the traditional japanese age system (e .g . years of career , years since entering a company , grade in school , and after death ) is mostly the corresponding day (e .g . the date of entering a company , the date of entering a school , and the date of person ' s death ). なお、記念日としての数え年（経歴、入社年数、学年等や没後など）の数え年の加算日は、その記念日の応当日（入社日、入学日、没日など）を基準とすることが多い。
as the new year ' s day is the base date in the traditional japanese age system , care is should be taken when calculating someone ' s age with this method because the new year ' s day under the gregorian calendar is different from that under the traditional japanese calendar that had been used until the gregorian calendar was introduced . 元日を基準とするのでグレゴリオ暦の導入以前は、暦法により元日が新暦に対し異なるため、数え年の計算には注意が必要である（単純に西暦で計算してはいけない）。
