Okay, that is comprehensible.

With the time period you added, I determined how many beneficiaries received @null.
I requested it with steemchillers SDS (https://sds0.steemworld.org/rewards_api/getRewardsSums/comment_benefactor_reward/null/1687899873-1689512937)

There are 7452.925 STEEM and 17664666.159899 VESTS burned.
With https://sds0.steemworld.org/chain_api/getDailyAverageShareRates you can get the average rates to convert VESTS in STEEM. I take an estimated average of 0.000568471975896668 STEEM per VESTS.
With this numbers I calculated a change per day of round 89138. It's closer to the prediction, but not as close as I would have hoped. I don't have any other ideas at the moment. Even with the burned SBD (0.092 SBD) in this time period, it won't match.