Uncertain, yet persistent, real rates of return to capital underpin one argument for using a declining schedule of social discount rates. Yet persistency is only present in approximately the first three-quarters of the time-series of US Treasury bond yields used by Newell and Pizer [37] to...

The case for using declining social discount rates when the future is uncertain is now widely accepted in both academic and policy circles. We present sharp upper and lower bounds for this term structure when we have limited knowledge about the nature of our uncertainty. At horizons beyond 75...