If we judge that inflationary pressures are restrained and the economy can achieve balanced growth, we can keep interest rates at very low levels.
Interest rates will stay at zero for a while, then move to extremely low levels before being adjusted according to economic conditions.
Interest rates will stay at zero for some time, then stay extremely low and go through an adjustment period.
The downward rigidity of nominal wages is often pointed out as a factor that prevents the smooth adjustment of real wages under very low inflation.
A low rate of inflation itself now poses a new challenge of achieving and promoting sustained economic growth in the global economy.