noun
total man-hours; total hours
Used in work, project, or statistical contexts to refer to the sum of hours worked by all people involved, without adjusting for overlapping time.
このプロジェクトの延べ時間は500時間を超えた。
The total man-hours for this project exceeded 500 hours.
ボランティアの延べ時間を集計する。
We tally up the total volunteer hours.
延べ人数 refers to the total number of people (headcount) over a period, while 延べ時間 refers to the total hours worked.
Compound of 延べ (nobe, 'total, cumulative') + 時間 (jikan, 'time, hours'). The prefix 延べ is used in counting contexts to indicate a cumulative total without deduplication.