IV.

Causes

Demand-pull inflation occurs when aggregate demand exceeds existing supplies, forcing price increases and pulling up wages, materials, and operating and financing costs. Cost-push inflation occurs when prices rise to cover total expenses and preserve profit margins. A pervasive cost-price spiral eventually develops as groups and institutions respond to each new round of increases. Deflation occurs when the spiral effects are reversed.

To explain why the basic supply and demand elements change, economists have suggested three substantive theories: the available quantity of money; the aggregate level of incomes; and supply-side productivity and cost variables. Monetarists believe that changes in price levels reflect fluctuating volumes of money available, usually defined as currency and demand deposits. They argue that, to create stable prices, the money supply should increase at a stable rate commensurate with the economy's real output capacity. Critics of this theory claim that changes in the money supply are a response to, rather than the cause of, price-level adjustments.

The aggregate level of income theory is based on the work of the British economist John Maynard Keynes, published during the 1930s. According to this approach, changes in the national income determine consumption and investment rates; thus, government fiscal spending and tax policies should be used to maintain full output and employment levels. The money supply, then, should be adjusted to finance the desired level of economic growth while avoiding financial crises and high interest rates that discourage consumption and investment. Government spending and tax policies can be used to offset inflation and deflation by adjusting supply and demand according to this theory. In the U.S., however, the growth of government spending plus “off-budget” outlays (expenditures for a variety of programs not included in the federal budget) and government credit programs have been more rapid than the potential real growth rate since the mid-1960s.

The third theory concentrates on supply-side elements that are related to the significant erosion of productivity. These elements include the long-term pace of capital investment and technological development; changes in the composition and age of the labor force; the shift away from manufacturing activities; the rapid proliferation of government regulations; the diversion of capital investment into nonproductive uses; the growing scarcity of certain raw materials; social and political developments that have reduced work incentives; and various economic shocks such as international monetary and trade problems, large oil price increases, and sporadic worldwide crop disasters. These supply-side issues may be important in developing monetary and fiscal policies.