Where interest is or may be payable, the creditor must ensure the contract specifies the rate as an annual interest rate (or describes how it is calculated), must not debit or require payment of interest before it accrues, must not charge more interest than the daily rate applied to each day's closing unpaid balance (with the end of day defined), and may charge default interest only on the amount in default and only while it remains in default, as section 40 provides.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.