Money, inflation and real values

Money is anything generally accepted in payment for goods and services and in settlement of debts within a community. Its main functions are to act as a medium of exchange, a unit of account, a store of value and a standard of deferred payment. Barter requires a double coincidence of wants: each party must want what the other offers. A widely accepted medium of exchange reduces this difficulty.

Good money is reasonably durable, portable, divisible and recognisable. Its usefulness as a store of value depends partly on stability in purchasing power. Inflation is a sustained increase in the general price level. It is not merely a rise in the price of one item. A local shortage might make tomatoes more expensive while many other prices remain unchanged. A price index tracks changes in the cost of a defined basket, but the actual effect on a household depends on its spending pattern.

The inflation rate is commonly calculated as the percentage change in a price index between two periods. If an index rises from 100 to 110, the increase is ten per cent. If it then rises from 110 to 121, the second increase is also ten per cent, not eleven per cent, because the comparison starts from 110. State the base of every percentage calculation clearly.

Nominal income is measured in current money terms. Real income adjusts for changes in the price level and indicates purchasing power. If money income rises by five per cent while prices rise by ten per cent, purchasing power falls. For an exact comparison, divide the income growth factor by the price growth factor; subtract one and express the result as a percentage. Simply subtracting the two rates gives an approximation.

Demand-pull inflation can occur when total spending presses against available productive capacity. Cost-push inflation can follow higher production costs. In practice, several forces can operate together. Inflation can reduce the purchasing power of fixed money incomes and make planning harder, but its effects differ between borrowers, lenders and households. Avoid claiming that every person gains or loses equally. Explain the mechanism and state the assumptions behind your conclusion.

What money does and what it is not

Money is anything generally accepted in settlement of transactions and debts in the relevant community. It serves as a medium of exchange, unit of account, store of value and standard of deferred payment. These functions help explain why barter can be inconvenient. In barter, a person wanting rice in exchange for cloth must find another person who wants that cloth and offers rice in the right quantity. This double coincidence of wants is difficult to arrange repeatedly across a complex economy.

An asset can be valuable without being generally accepted as money. A house may store wealth, but it is not normally used to pay a bus fare. A bank deposit can function as money when people can make payments from it, while a payment card or transfer application is usually an instrument for accessing funds rather than a separate stock of money. An economy can have several measures of money supply with different levels of liquidity. Use the definition supplied in the question rather than assume every financial asset belongs to every measure.

Price levels, inflation and the cost of living

Inflation is a sustained increase in the general price level. A higher price for one product does not by itself establish general inflation. A temporary shortage of tomatoes may change their relative price while many other prices remain stable. A price index combines a selected set of prices using stated weights and a base period. In a simple fixed-basket exercise, the index is the current cost of the basket divided by its base-period cost, multiplied by 100. The basket and weights determine what the index measures.

Suppose a household basket cost ₦40,000 in the base period and ₦50,000 in the comparison period. Its index is 125, meaning the basket costs 25% more than in the base period. If an index rises from 120 to 132 between two adjacent years, the inflation rate is (132 − 120) ÷ 120 × 100 = 10%. Dividing by 100 would incorrectly give 12%. Distinguish an index-point change from a percentage change and state the period to which the rate refers.

Disinflation means that the rate of inflation falls while prices may still be rising. If inflation falls from 15% to 8%, the price level generally continues to rise, but more slowly. Deflation is a fall in the general price level. A negative inflation rate indicates deflation over that measurement period. A lower positive rate does not restore earlier prices. This distinction matters when interpreting a report that inflation has eased, because households may still face higher prices than a year before.

Causes and distributional effects

Demand-pull explanations emphasise aggregate spending growing relative to the economy's ability to supply output. Cost-push explanations emphasise higher production costs or supply disruptions. Imported input prices and exchange-rate movements can also transmit price pressure. These channels may occur together, so a complete explanation links an initial cause to costs, demand or expectations instead of treating one label as a complete account of every episode. Do not infer a precise cause from the price index alone.

Inflation redistributes purchasing power unevenly. Someone receiving a fixed nominal income can buy less if prices rise and that income does not adjust. A borrower with a fixed nominal debt may repay in money with lower purchasing power, while the lender may lose in real terms if interest does not compensate for inflation. These effects depend on whether inflation was anticipated, whether contracts are indexed and how individual prices and earnings change. It is too broad to say that every borrower always gains or every firm always loses.

Nominal values and real values

A nominal value is measured in current money. A real value adjusts for a relevant price index. If a wage rises from ₦80,000 to ₦88,000, nominal growth is 10%. If the relevant price index also rises by 10%, purchasing power is unchanged in that simplified example. To express current income in base-period purchasing power, divide the nominal amount by the index and multiply by 100. With nominal income ₦90,000 and index 125, real income in base-period prices is ₦72,000.

For exact real growth over a period, compare the ratio of nominal growth factors with the price growth factor: real growth = (1 + nominal growth rate) ÷ (1 + inflation rate) − 1. With a 12% nominal wage rise and 8% inflation, real growth is 1.12 ÷ 1.08 − 1, about 3.70%. Subtracting 8 from 12 gives a rough approximation of 4%, but it is not the exact calculation. State whether a question expects the precise result or the common approximation.

Self-check: an index falls from 150 to 145. This is a fall in the measured price level, not merely a lower positive inflation rate. Self-check: an income of ₦60,000 at index 120 has base-price purchasing power of ₦50,000. When writing an explanation, identify who receives money, the price measure used and the relevant dates. Avoid inserting unverified contemporary inflation statistics into a conceptual answer; all numerical figures here are hypothetical teaching examples.