"Measuring the Natural Rate of Interest Redux,"

The Federal Reserve Bank of San Francisco published a working paper this month, "Measuring the Natural Rate of Interest Redux," in which it introduced the potential for using both negative short-end rates coupled with another round of quantitative easing (QE) focused at the long end, as a response to the next recession.

http://www.frbsf.org/economic-research/files/wp2015-16.pdf

Thomas Laubach
Board of Governors of the Federal Reserve System
and
John C. Williams
Federal Reserve Bank of San Francisco
October 14, 2015

 Persistently low real interest rates have prompted the question whether low interest rates are here to stay. This essay assesses the empirical evidence regarding the natural rate of interest in the United States using the Laubach-Williams model. Since the start of the Great Recession, the estimated natural rate of interest fell sharply and shows no sign of recovering. These results are robust to alternative model specifications. If the natural rate remains low, future episodes of hitting the zero lower bound are likely to be frequent and long-lasting. In addition, uncertainty about the natural rate argues for policy approaches that are more robust to mismeasurement of natural rates.