NAIRU

NAIRU is an acronym for non-accelerating inflation rate of unemployment, and refers to a level of unemployment below which inflation rises. It was first introduced as NIRU (non-inflationary rate of unemployment) by Franco Modigliani and Lucas Papademos in 1975, as an improvement over the "natural rate of unemployment" concept, which was proposed earlier by Milton Friedman.

Monetary policy conducted under the assumption of a NAIRU involves allowing just enough unemployment in the economy to prevent inflation rising above a given target figure. Prices are allowed to increase gradually and some unemployment is tolerated.

An early form of NAIRU is found in the work of Abba P. Lerner (Lerner 1951, Chapter 14), who referred to it as "low full employment" attained via the expansion of aggregate demand, in contrast with the "high full employment" which adds incomes policies (wage and price controls) to demand stimulation.

The concept arose in the wake of the popularity of the Phillips curve which summarized the observed negative correlation between the rate of unemployment and the rate of inflation (measured as annual nominal wage growth of employees) for number of industrialised countries with more or less mixed economies. This correlation (previously seen for the U.S. by Irving Fisher) persuaded some analysts that it was impossible for governments simultaneously to target both arbitrarily low unemployment and price stability, and that, therefore, it was government's role to seek a point on the trade-off between unemployment and inflation which matched a domestic social consensus.

During the 1970s in the United States and several other industrialized countries, Phillips curve analysis became less popular, because inflation rose at the same time that unemployment rose (see stagflation).

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