The Past as Prologue

The Federal Reserve raised the federal funds rate, the rate banks charge other banks to borrow reserves on an overnight basis, from 0 and 0.25% per year to 0.25 and 0.50% per year.
They are attempting to achieve their dual mandate of spurring the United States economy to full employment and keeping the inflation rate in check, which they define as 2% per year.
However, if we look at data prior to 1913, when the Fed was created, we see that short term interest rates, negotiated between willing parties, were never below 2% per year.
This level could be used as an effective lower bound for future Federal Reserve policy, using the past as prologue.