I based this on an 80/20 split between post and curation rewards.
$845 / 13 posts = $65
65 x 80% post reward = $52/post
$52 x 50% (post rewards split between SBD and SP) = 26 SBD
26 x 70% = 18.2 SBD
18.2 x 13 posts = 236.6 SBD
So it would be a little less than the stated amount, but I’m adding the payout from this post to the total, which should get us pretty close to the target goal.
There are also direct donations coming in from some generous friends and other Steem users.
You wrote:
"That means the post rewards would need to be the approximate equivalent of 65-70 SBD per contest post."
But what you meant is $65 per post instead of 65 SBD per post. That gives a whole kind of different calculation. Basically the one you explained to me.
However at this moment there is a detail that causes a little twitch. Part of the SBD pay out is done in liquid Steem. So without calculating it I'm 100% certain you need a higher average post pay out to reach the 250 SBD goal.
Now I make my next assumption, I think the SP+liquid Steem pay out is what you earn, correct?
If so that would mean you end up with 26/1.7=15.29SP on average per post. Multiplied with 13 gives 199 SP. Add up 25% (currently it's above 30%) for liquid Steem pay out and you can earn close to 250 Steem.
It's really remarkable that you can pull this off. I have to hang around 2.5 years on Steemit to earn such an amount.
Btw, don't get me wrong by thinking I disagree that you should earn this. I just like numbers and investigation as I am an economist. So keep up the good work!