Article 20 requires Member States to sell CBAM certificates to authorised CBAM declarants in their Member State via a common central platform, with the certificates valid only in the year of purchase + the year of cancellation. Article 21 sets the price of CBAM certificates at the weekly average of the EU ETS auction closing prices for the previous calendar week (the Commission publishes the price weekly).
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.