Inflation reflects itself first in a lowering of the actual rate of interest beneath the natural rate.

FORBES: Why Interest Rates Tell Lies About Inflation, Growth And Just About Everything Else

My good friend and sometime mentor, Brian Wesbury, argues that the natural rate of interest is the same as the nominal GDP growth rate.

FORBES: What Is the Liquidity Premium? What Does It Mean?

As US unemployment continues to head south towards its natural rate, and the prospect of an interest rate spike is a possibility, there is one factor that may avert, or at least moderate, an interest rate spike: The yen tsunami, i.e.

FORBES: What May Keep US Interest Rates From Spiking

Even the most hawkish members of the Fed's interest-rate setting committee believe that the U.S. natural unemployment rate is below 6.5%.

WSJ: Wonk Wars: How Big Are EU Deficits?