OK, so amount of voting power at the start of voting session does not determnate the profit.
With lower voting power the vote is worth less but you can make more 100% votes because each vote deplates the total voting power by lower amount.
For example with 100% vp you can make 10 x 1 SBD upvotes.
With 50% vp you can make 20 x 0.5 SBD upvotes - the outcome (profit) is the same.
That being said, @tipu starts each voting session with 92% vp and continues to vote until a total of 20% vp is used - then proceeds to recover those 20% so that the next session starts again at 92% the same hour next day.
So 20% of total voting power is used and recovered each day and those 20% used will generate the same profit no matter if the voting starts from 100% or 30%, for example.
Hope this makes sense, it was a long day :)
Ahh makes sense. This is very intuitive I made fun say.