Until the 1970s, many economists believed that there was a stable inverse relationship between inflation and unemployment. They believed that inflation was tolerable because it meant the economy was growing and unemployment would be low. Their general belief was that an increase in the demand for goods would drive up prices, which in turn would encourage firms to expand and hire additional employees. This would then create additional demand throughout the economy.

According to this theory, if the economy slowed, unemployment would rise, but inflation would fall. Therefore, to promote economic growth, a country's central bank could increase the money supply to drive up demand and prices without being terribly concerned about inflation. According to this theory, the growth in money supply would increase employment and promote economic growth. These beliefs were based on the Keynesian school of economic thought, named after twentieth-century British economist John Maynard Keynes.

In the 1970s, Keynesian economists had to reconsider their beliefs as the U.S. and other industrialized countries entered a period of stagflation. Stagflation is defined as slow economic growth occurring simultaneously with high rates of inflation. In this article, we'll examine 1970s stagflation in the U.S., analyze the Federal Reserve's monetary policy (which exacerbated the problem) and discuss the reversal in monetary policy as prescribed by Milton Friedman that eventually brought the U.S. out of the stagflation cycle.

1970s Economy

When people think of the U.S. economy in the 1970s the following things come to mind:

In December 1979, the price per barrel of West Texas Intermediate crude oil topped $100 (in 2016 dollars) and peaked at $117.71 the following April. That price level would not be exceeded for 28 years.

Inflation was high by U.S. historical standards: core consumer price index (CPI) inflation – that is, excluding food and fuel – reached an annual average of 12.4% in 1980. Unemployment was also high, and growth uneven; the economy was in recession in 1970 and again from 1974 to 1975.

The prevailing belief as promulgated by the media has been that high levels of inflation were the result of an oil supply shock and the resulting increase in the price of gasoline, which drove the prices of everything else higher. This is known as cost push inflation. According to the Keynesian economic theories prevalent at the time, inflation should have had an inverse relationship with unemployment, and a positive relationship with economic growth. Rising oil prices should have contributed to economic growth. In reality, the 1970s was an era of rising prices and rising unemployment; the periods of poor economic growth could all be explained as the result of the cost push inflation of high oil prices, but it was unexplainable according to Keynesian economic theory. (See also, Cost-Push Inflation Versus Demand-Pull Inflation.)

A now well-founded principle of economics is that excess liquidity in the money supply can lead to price inflation; monetary policy was expansive during the 1970s, which could explain the rampant inflation at the time.

Inflation: Monetary Phenomenon

Milton Friedman was an American economist who won a Nobel Prize in 1976 for his work on consumption, monetary history and theory, and for his demonstration of the complexity of stabilization policy. In a 2003 speech, the chairman of the Federal Reserve, Ben Bernanke, said, "Friedman's monetary framework has been so influential that in its broad outlines at least, it has nearly become identical with modern monetary theory … His thinking has so permeated modern macroeconomics that the worst pitfall in reading him today is to fail to appreciate the originality and even revolutionary character of his ideas in relation to the dominant views at the time that he formulated them."

Milton Friedman did not believe in cost push inflation. He believed that "inflation is always and everywhere a monetary phenomenon." In other words, he believed prices could not increase without an increase in the money supply. To get the economically devastating effects of inflation under control in the 1970s, the Federal Reserve should have followed a constrictive monetary policy. This finally happened in 1979 when Federal Reserve Chairman Paul Volcker put the monetarist theory into practice. This drove interest rates to double-digit levels, reduced inflation and sent the economy into a recession.

In a 2003 speech, Ben Bernanke said about the 1970s, "the Fed's credibility as an inflation fighter was lost and inflation expectations began to rise." The Fed's loss of credibility significantly increased the cost of achieving disinflation. The severity of the 1981-82 recession, the worst of the postwar period, clearly illustrates the danger of letting inflation get out of control.

This recession was so exceptionally deep precisely because of the monetary policies of the preceding 15 years, which had unanchored inflation expectations and squandered the Fed's credibility. Because inflation and inflation expectations remained stubbornly high when the Fed tightened, the impact of rising interest rates was felt primarily on output and employment rather than on prices, which continued to rise. One indication of the loss of credibility suffered by the Fed was the behavior of long-term nominal interest rates. For example, the yield on 10-year Treasuries peaked at 15.3% in September 1981 - almost two years after Volcker's Fed announced its disinflationary program in October 1979, suggesting that long-term inflation expectations were still in the double digits. Milton Friedman gave credibility back to the Federal Reserve. (For further reading, see The Federal Reserve.)

Bottom Line

The job of a central banker is challenging to say the least. Economic theory and practice has improved greatly thanks to economists like Milton Friedman, but challenges continuously arise. As the economy evolves, monetary policy, and how it is applied, must continue to adapt to keep the economy in balance.

For more on Milton Friedman and monetary policy, see Free Market Maven: Milton Friedman and our FAQ, What do Keynes and Friedman have to do with fiscal and monetary policy?

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