I was confused because I only use the INTERNAL MARKET to easily get the current value of STEEM/SP. Got you. Haha! I used your formula and the result is the same when I get the ratio (1SBD/RATIO).
I am still referring to the rewards, the 50/50 reward. The 50% SBD to buy STEEM and POWER UP (add SP).
My goodness I hate this Steemit math it reminds me of my college days :-D
So what formula are you using to calculate STU to SP?
Reference above screenshot:
SBD/1.174572 😅
(SBD/price of SBD/STEEM)
That price/ratio is automatically provided at Steemit "Currency Market" I only input amount of Steem when buying 😅