The Number Of People, The Amount Of People
noun
The person count is the number of people. Don't confuse this with the "population" or something like that, though. This is more like "how many people are at this event?" What's the 人数, you know?
にんずう
This is a jukugo word, which usually means on'yomi readings from the kanji. Note that rendaku turns すう into ずう, and since 人 has two on'yomi readings, here's a mnemonic to help you remember which one to use: Do you know the number of people at Nintendo (にん)? It's a big mystery, which is why they hired you to count every single one of them. Good luck!
この会社のスタッフの人数は二十人です。
The number of staff at this company is twenty people.
今週の出社人数は少し下がった。
The number of people coming to work has dropped a little this week.
去年のイベントではスタッフの人数が足りなかったのに、今年は多すぎるくらいです。
There weren't enough staff at last year's event, but this year there are too many.