How to get full coverage of the community through the VKontakte API?

Question

API

I look at the full coverage for the month in the internal statistics of VKontakte https://vk.com/stats?act=reach&gid=79824818 and I have 914 users in August.

I'm trying to get this data via the API, an example of the data I'm passing:
https://vk.com/dev/stats.get?params[group_id]=7982...
I'm getting a response https://pastebin.com/wxF57vpL
There are completely different numbers and do not match in any way :(
In the answer, period_from and period_to are shifted, i.e. there is no period from August 1 to August 31, but there is from August 5 to September 5.
How to get full coverage through the API, which will coincide with that What can be seen in the office?