Price level in the context of "Deflation"

Real income is the income of individuals or nations after adjusting for inflation. It is calculated by dividing nominal income by the price level. Real variables such as real income and real GDP are variables that are measured in physical units, while nominal variables such as nominal income and nominal GDP are measured in monetary units. Therefore, real income is a more useful indicator of well-being since it measures the amount of goods and services that can be purchased with the income. Growth of real income is related to real gross national income per capita growth.

According to the classical dichotomy theory, real variables and nominal variables are separate in the long run, so they are not influenced by each other. In other words, if the nominal starting income was 100 and there was 10% inflation (general rise in prices, for example, what cost 10 now costs 11), then with nominal income of still 100, one can buy roughly 9% less; so if nominal income was not adjusted for inflation (did not rise by 10%), real income has dropped by approximately 9%. But if the classical dichotomy holds, nominal income will eventually go up by 10%, leaving real income unchanged from its original value.

A price index (plural: "price indices" or "price indexes") is a normalized average (typically a weighted average) of price relatives for a given class of goods or services in a specific region over a defined time period. It is a statistic designed to measure how these price relatives, as a whole, differ between time periods or geographical locations, often expressed relative to a base period set at 100.

Price indices serve multiple purposes. Broad indices, like the Consumer price index, reflect the economy’s general price level or cost of living, while narrower ones, such as the Producer price index, assist producers with pricing and business planning. They can also guide investment decisions by tracking price trends.  

A supply shock is an event that suddenly increases or decreases the supply of a commodity or service, or of commodities and services in general. This sudden change affects the equilibrium price of the good or service or the economy's general price level.

In the short run, an economy-wide negative supply shock will shift the aggregate supply curve leftward, decreasing the output and increasing the price level. For example, the imposition of an embargo on trade in oil would cause an adverse supply shock, since oil is a key factor of production for a wide variety of goods. A supply shock can cause stagflation due to a combination of rising prices and falling output. The 1973 Oil Crisis is often used as the exemplar case of a supply shock, when OPEC restrictions on production and sale of petroleum resulted in fuel shortages throughout the developed world.

Monetarism is a school of thought in monetary economics that emphasizes the role of policy-makers in controlling the amount of money in circulation. It gained prominence in the 1970s, but was mostly abandoned as a direct guidance to monetary policy during the following decade because of the rise of inflation targeting through movements of the official interest rate.

The monetarist theory states that variations in the money supply have major influences on national output in the short run and on price levels over longer periods. Monetarists assert that the objectives of monetary policy are best met by targeting the growth rate of the money supply rather than by engaging in discretionary monetary policy. Monetarism is commonly associated with neoliberalism.

Food prices refer to the average price level for food across countries, regions and on a global scale. Food prices affect producers and consumers of food. Price levels depend on the food production process, including food marketing and food distribution. Fluctuation in food prices is determined by a number of compounding factors. Geopolitical events, global demand, exchange rates, government policy, diseases and crop yield, energy costs, availability of natural resources for agriculture, food speculation, changes in the use of soil and weather events directly affect food prices. To a certain extent, adverse price trends can be counteracted by food politics.

The consequences of food price fluctuation are multiple. Increases in food prices, or agflation, endangers food security, particularly for developing countries, and can cause social unrest. Increases in food prices is related to disparities in diet quality and health, particularly among vulnerable populations, such as women and children.

In economics, aggregate demand (AD) or domestic final demand (DFD) is the total demand for final goods and services in an economy at a given time. It is often called effective demand, though at other times this term is distinguished. This is the demand for the gross domestic product of a country. It specifies the amount of goods and services that will be purchased at all possible price levels. Consumer spending, investment, corporate and government expenditure, and net exports make up the aggregate demand.

The aggregate demand curve is plotted with real output on the horizontal axis and the price level on the vertical axis. While it is theorized to be downward sloping, the Sonnenschein–Mantel–Debreu results show that the slope of the curve cannot be mathematically derived from assumptions about individual rational behavior. Instead, the downward sloping aggregate demand curve is derived with the help of three macroeconomic assumptions about the functioning of markets: Pigou's wealth effect, Keynes' interest rate effect and the Mundell–Fleming exchange-rate effect. The Pigou effect states that a higher price level implies lower real wealth and therefore lower consumption spending, giving a lower quantity of goods demanded in the aggregate. The Keynes effect states that a higher price level implies a lower real money supply and therefore higher interest rates resulting from relevant market equilibrium condition, in turn resulting in lower investment spending on new physical capital and hence a lower quantity of goods being demanded in the aggregate.

In economics, the long-run is a theoretical concept in which all markets are in equilibrium, and all prices and quantities have fully adjusted and are in equilibrium. The long-run contrasts with the short-run, in which there are some constraints and markets are not fully in equilibrium. More specifically, in microeconomics there are no fixed factors of production in the long-run, and there is enough time for adjustment so that there are no constraints preventing changing the output level by changing the capital stock or by entering or leaving an industry. This contrasts with the short-run, where some factors are variable (dependent on the quantity produced) and others are fixed (paid once), constraining entry or exit from an industry. In macroeconomics, the long-run is the period when the general price level, contractual wage rates, and expectations adjust fully to the state of the economy, in contrast to the short-run when these variables may not fully adjust.

In economics, a price support may be either a subsidy, a production quota, or a price floor, each with the intended effect of keeping the market price of a good higher than the competitive equilibrium level, usually by a government.

In the case of a price control, a price support refers to the minimum legal price a seller may charge, typically placed above equilibrium. It is the support of certain price levels at or above market values by the government.