From the Islamic finance industry perspective, an important criterion for the industry wide adoption of any benchmark, particularly one that is published every business day, is the simplicity, reliability and robustness of its methodology.
A key maxim of Islamic jurisprudence suggests that in the matter of commercial transactions, everything is deemed permissible unless explicitly stated otherwise. As long as the transacting parties adhere to the principles of Islamic jurisprudence while applying the benchmark to their transaction, it is acceptable to utilize a consensus methodology. In place of risk free rate or base rate of expected return on investment, some thinkers in Islamic finance suggest the possible use of Zakat rate.
Islamic Economics Project 