Okun's law is a robust modelling tool, which held empirically in many economies worldwide, including some in the eurozone, during and after the financial crisis, a team of researchers has argued. But, say the authors of an occasional paper published by the European Central Bank (ECB) on August 10, the relationship is "surprisingly difficult" to recreate in structural models. Macroeconomic modellers need to find more sophisticated ways of simulating how financial frictions affect the labour