Wow that sucks!
Same thing just happened to me today on my post.
It was the first successful posting I've had on Steemit and it was up above $5700 at its height (no screenshot like you). Anyway, come payout I received $4,545. I didn't really care that much since 4K+ is still a lot of money, but I can't explain the drop. There must be some logical explanation like bot manipulation or a portion of the payout going to commenters.
Regardless I'm a noob and I am curious to hear what you find out...
Believe it or not, YOUR drop sounds like expected behavior, actually.
The earnings get shared among the author and the curators.
But 75% goes to the author (which is then split 50/50 between SBD and SP), while only 25% goes to the curators. That looks about right.
I was expecting about a $940 payout (about $470 SBD, then remaining 50% as SP). So I ended up only getting paid about 15% of what was expected.
Thanks for the detailed explanation. I figured it was something like that and I probably should have researched the payout algo on my own. Anyway, I hope you are able to determine why you weren't able to get the payout you expected.
Good luck!
Mine seems to have flipped the 25/75 rules to 75/25.
Maybe not, but that's what it feels like.