your calculation is correct except of one little mistake - the author reward is right now around 75% SBD and 25% STEEMPOWER.
We've explained this here: https://steemit.com/steem/@smartsteem/guide-author-payout-ratio-how-much-sbd-and-steempower-as-author-reward
If you have any more questions, please feel free to ask :)
RE: Guide: Upvote-Calculation with SBD & STEEM for @smartmarket