I'm not going to post these every day, but since it's a weekend, here's today's graph. After the first complete day of burning, the SBD curve already shows a bit of a dip. As anticipated, there are no visible changes in direction from the other curves.

By my estimate, the total SBD supply, in and out of the SPS, would need to get down in the neighborhood of 4.9 million before all of the debt buffer would get soaked up and thevirtual supply and Collateralized STEEM would start dropping (assuming current values for the price of STEEM and current_supply). (This is consistent with this calculation from @moecki.)

Unless/until the price of STEEM rises above the haircut price, burning SBDs is simply a debt transfer from the burned SBDs to the SBDs that remain. (Interestingly, this suggests that some debt is being transferred from the SPS to SBD holders outside of the SPS.)

Edited to add: At the end of this burn exercise, I estimate the haircut price will be lowered to around $0.138.