No-one would think of reducing the actual decision-making process to a mathematical formula, least of all one devised by an international committee. If that’s true for monetary policy, then it’s much more true for financial stability policy, where the complexities are even greater.
There’s nothing in financial stability policy, for example, that corresponds to the core monetary policy objective of a numerical inflation target, or the single instrument of a policy interest rate: financial stability policy has a wide range of instruments at its disposal, and there’s no single summary indicator of aggregate financial risk.