"This is most obvious," writes The Economist, "in the case of bonds: a yield of 2% means the nominal return if you hold the bond to maturity will be 2%. The real return may even be negative if inflation rises."
"Worse still, there is always the chance that profits or valuations will return to their historical norms. If that happens, Deutsche reckons the average real return from equities over the next ten years will be negative. The same is true for Treasury bonds, European corporate bonds and American residential property."
"We are not just data-dependent but uncontrollable foreign economy-dependent."