Bullard, James

[W]hile the monetary base has expanded at an extraordinarily fast pace during the fall and winter, much of that expansion has been closely related to the Fed’s lender-of-last-resort function, and cannot be counted on to keep expectations of disinflation and deflation at bay. Because of this, the Fed needs a more systematic method of keeping the persistent component of monetary base growth rates elevated in order to combat the risk of a deflationary trap.

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“As I have discussed, the Fed’s balance sheet has grown at an astounding rate since September of last year, and the monetary base has more than doubled. But the new, temporary, lender-of-last-resort programs are blurring the meaning of this picture. A temporary increase in the monetary base, by itself, would not normally be considered inflationary. The increase would have to be expected to be sustained in the future in order to have an impact. Much, but not all, of the recent increase in the balance sheet can reasonably be viewed as temporary. The outright purchases of agency debt and MBS are likely to be more persistent, however, and it is these purchases that may provide enough expansion in the monetary base to offset the risk of further disinflation and possible deflation. The quantitative effects of policy actions in this new environment are more uncertain than normal, but nevertheless these less-conventional policies can have every bit as powerful an impact on the economy as changes in the intended federal funds rate.