Brief History of Macroeconomic Thought and Policy

Read this chapter to examine macroeconomic attitudes towards economic policies of the three main schools of economic thought: Classical, Keynesian, and Monetarist. Also, learn about modern day interpretations of the main ideas.

2. Keynesian Economics in the 1960s and 1970s

The Monetarist Challenge

The idea that changes in the money supply are the principal determinant of the nominal value of total output is one of the oldest in economic thought; it is implied by the equation of exchange, assuming the stability of velocity. Classical economists stressed the long run and thus the determination of the economy's potential output. This meant that changes in the price level were, in the long run, the result of changes in the money supply.

At roughly the same time Keynesian economics was emerging as the dominant school of macroeconomic thought, some economists focused on changes in the money supply as the primary determinant of changes in the nominal value of output. Led by Milton Friedman, they stressed the role of changes in the money supply as the principal determinant of changes in nominal output in the short run as well as in the long run. They argued that fiscal policy had no effect on the economy. Their "money rules" doctrine led to the name monetarists. The monetarist school holds that changes in the money supply are the primary cause of changes in nominal GDP.

Monetarists generally argue that the impact lags of monetary policy – the lags from the time monetary policy is undertaken to the time the policy affects nominal GDP – are so long and variable that trying to stabilize the economy using monetary policy can be destabilizing. Monetarists thus are critical of activist stabilization policies. They argue that, because of crowding-out effects, fiscal policy has no effect on GDP. Monetary policy does, but it should not be used. Instead, most monetarists urge the Fed to increase the money supply at a fixed annual rate, preferably the rate at which potential output rises. With stable velocity, that would eliminate inflation in the long run. Recessionary or inflationary gaps could occur in the short run, but monetarists generally argue that self-correction will take care of them more effectively than would activist monetary policy.

While monetarists differ from Keynesians in their assessment of the impact of fiscal policy, the primary difference in the two schools lies in their degree of optimism about whether stabilization policy can, in fact, be counted on to bring the economy back to its potential output. For monetarists, the complexity of economic life and the uncertain nature of lags mean that efforts to use monetary policy to stabilize the economy can be destabilizing. Monetarists argued that the difficulties encountered by policy makers as they tried to respond to the dramatic events of the 1970s demonstrated the superiority of a policy that simply increased the money supply at a slow, steady rate.

Monetarists could also cite the apparent validity of an adjustment mechanism proposed by Milton Friedman in 1968. As the economy continued to expand in the 1960s, and as unemployment continued to fall, Friedman said that unemployment had fallen below its natural rate, the rate consistent with equilibrium in the labor market. Any divergence of unemployment from its natural rate, he insisted, would necessarily be temporary. He suggested that the low unemployment of 1968 (the rate was 3.6% that year) meant that workers had been surprised by rising prices. Higher prices had produced a real wage below what workers and firms had expected. Friedman predicted that as workers demanded and got higher nominal wages, the price level would shoot up and unemployment would rise. That, of course, is precisely what happened in 1970 and 1971. Friedman's notion of the natural rate of unemployment buttressed the monetarist argument that the economy moves to its potential output on its own.

Perhaps the most potent argument from the monetarist camp was the behavior of the economy itself. During the 1960s, monetarist and Keynesian economists alike could argue that economic performance was consistent with their respective views of the world. Keynesians could point to expansions in economic activity that they could ascribe to expansionary fiscal policy, but economic activity also moved closely with changes in the money supply, just as monetarists predicted. During the 1970s, however, it was difficult for Keynesians to argue that policies that affected aggregate demand were having the predicted impact on the economy. Changes in aggregate supply had repeatedly pushed the economy off a Keynesian course. But monetarists, once again, could point to a consistent relationship between changes in the money supply and changes in economic activity.

Figure 17.6 "M2 and Nominal GDP, 1960–1980" shows the movement of nominal GDP and M2 during the 1960s and 1970s. In the figure, annual percentage changes in M2 are plotted against percentage changes in nominal GDP a year later to account for the lagged effects of changes in the money supply. We see that there was a close relationship between changes in the quantity of money and subsequent changes in nominal GDP.

Figure 17.6 M2 and Nominal GDP, 1960–1980

The chart shows annual rates of change in M2 and in nominal GDP, lagged one year. The observation for 1961, for example, shows that nominal GDP increased 3.5% and that M2 increased 4.9% in the previous year, 1960. The two variables showed a close relationship in the 1960s and 1970s.

Monetarist doctrine emerged as a potent challenge to Keynesian economics in the 1970s largely because of the close correspondence between nominal GDP and the money supply. The next section examines another school of thought that came to prominence in the 1970s.