Very interesting ups and downs in terms of payment in USD specially the drop that happened after 2018. The market seems to still lack standards with payments being all over the place and still being low considering how much ads normally cost specially when they get so many impressions.

Just do it. It's not like you'll hurt his feelings by asking. You'll either get an answer or you won't.
This is an example that you can succeed in any field as long as you dedicate enough time and effort. 10 years ago, if you told your parents that you're going to sit at home counting posts on a forum about bitcoin they'd laugh at you and tell you to get a real job.

What always struck me in signature campaigns is how they balance the payments to attract people from first and third world. For someone from Pakistan or Ghana, a $20 a week would look good but you wouldn't get a US or EU citizen to do the job so campaigns have to adjust the payments to make it work. It looks like $50-60 a week is where the demand is at the moment.

It's still a signature campaign, isn't it?  

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Now I am not good with data, if there was opportunity, I could study and get some knowledge about data, statistics or data science. It seems interesting.
I could as well go ahead and check out the impact of the emergence of the OG sig campaign managers (Hhampuz and yahoo62278). Just imagine for a moment, what It would be like in the last 4-5 years without those two guys.

When DarkStar_ made this announcement:


Bitcoin price was around $35k.

0.0375 times $34k gives $1312 per week.

Correct me if I am wrong, but looking back it is not surprising to decrease in rates and pay in USD. The price rose steadily in the following months, so that if the change had not occurred, the weekly payment could have almost doubled.

Very nice compilation of Bitcointalk Signature Campaigns.  
I've linked your research in our German local board because it's very interesting.

But one question:

Since you calculated for your statistics only campaigns when they were started as explained here:

Would you be interested to update at least some recent years (starting from 2017) and provide an additional calculation where the most rewarded campaigns are always included (as long a such campaigns were running?). So, Chipmixer would be included from 2017 to 2022 while rewards were lowered from 2021 on.
But I don't know if it would be too much work fo you.

Decision is up to you.