I first thought the numbers were for the forum's entire history, but if that's just for last year, what are the total numbers?

If anyone's interested, here are all time top50 reporters' lists:

as of 2016/07/01:
https://bitcointalk.org/index.php?topic=1532365.msg15429237#msg15429237

as of 2017/09/12:
https://bitcointalk.org/index.php?topic=2166379.msg21740582#msg21740582

Actually, comparing with previous numbers it looks like new numbers could be for total report counts as of 2018/12/31.

edit: 2nd link fixed