There is a well-established relationship, called the McCallum Rule, between the growth rate of the monetary base and the growth rate of NGDP.

FORBES: This Economic Recovery Is Surely Different: It's FUBAR*

Applying the McCallum Rule to the conditions of late 2008, the Fed would have targeted to increase the monetary base by 6.32% during 2009 in order to produce 5% NGDP growth.

FORBES: This Economic Recovery Is Surely Different: It's FUBAR*

Dr. McCallum argues that his rule suggest a policy of monetary easing when velocities are declining.

FORBES: Keynesianism in 1954