Macrofoundations for A (Near) 2% Inflation Target

Economists have argued that a long-term inflation target near 2% is optimal (Summers, 1991; Fischer, 1996; Goodfriend, 2002; Coenen et al., 2003; Bernanke, 2003). However, these arguments are really about why a low positive inflation rate is ideal to avoid a deflationary trap, not explaining why the specific value of 2% (or a value near it) happens to be the optimal long-run inflation rate. In line with the transaction motive literature (Baumol, 1952 and Tobin, 1956), I postulate that new forms of money and technological progress generate cost savings in the transaction technology by comparison to barter. I derive the optimal velocity of money, which depends on real GDP/capita and the net return on depository institutions’ assets. As long as progress is on average biased towards new forms of money, the velocity of money will grow at a pace slower than long-term real GDP/capita growth; i.e. less than 2%. The empirical tests using Johansen’s (1995) VECM approach for the U.S. over the period 1959-2007 confirm that this is indeed the case. Along with a parameter representing the type of bias in the technical progress affecting transactions, the depository institutions’ overall mean leverage ratio also appears as a key parameter in the long-run equilibrium equation describing the behavior of the velocity of narrow money (M1, M1RS and M1S). I show that a ‘naïve’ Friedman k-percent monetary rule that aims at growing the money supply at the same rate as real GDP naturally leads to a rate of inflation equal to the rate of velocity growth. Hence, setting an inflation target near but below 2% makes economic sense. In spite of previously held beliefs, a money growth objective is compatible with an interest-targeting objective; i.e. a derived Taylor (1993) type rule. A Taylor rule that embeds the optimal inflation target defined here is more flexible to account for possible changes in velocity vs. a pure money growth rule.