def sp_to_sbd(self, sp, post_rshares=0, voting_power=STEEM_100_PERCENT, vote_pct=STEEM_100_PERCENT, not_broadcasted_vote=True, use_stored_data=True):
        """ Obtain the resulting SBD vote value from Steem power

            :param number steem_power: Steem Power
            :param int post_rshares: rshares of post which is voted