That is a case of correlation is not causation, and it's essentially one of the biggest problems faced by macroeconomists and policymakers alike (alongside... m

That is a case of correlation is not causation, and it's essentially one of the biggest problems faced by macroeconomists and policymakers alike (alongside... many other fields, of course). Unfortunately there's no way to determine causality without extensive experimentation, and more unfortunately monetary and fiscal policy do not allow for the same playgrounds that other fields have access to. We know certain policies work, but for those what's then missing is to what extent.