What is inflation? Inflation is a sustained increase in the general level of prices for goods and services over time. When inflation occurs, money generally buys fewer goods and services than before. This is a fall in purchasing power. Inflation does not mean every price rises at the same rate: some prices may rise quickly, some may remain unchanged and others may fall.
The important distinction is between one price changing and the overall price level increasing. If the price of one brand of coffee rises because of a supply shortage, that alone is not enough to show that the whole economy has inflation. Economists look at a broad group of prices, usually summarised by a price index such as the Consumer Price Index (CPI).
Quick notes: Inflation measures the rate at which the general price level rises. Deflation means the general price level falls. Disinflation means inflation is still positive but its rate is slowing. CPI tracks price changes in a defined basket of goods and services. Your personal inflation experience may differ from the national average because households buy different things. Lower inflation does not mean prices have returned to their previous level.
How inflation is measured
A statistical agency collects prices for a representative basket of goods and services and compares the basket’s cost over time. The basket may include food, transport, clothing, healthcare, education, recreation and other household purchases. Each category receives a weight based on its importance in household spending. A price index summarises these changes.
The annual inflation rate is commonly calculated as the percentage change in a price index compared with the same period a year earlier. Monthly inflation compares one month with the previous month. These measures answer different questions: a monthly movement can be small while the annual rate remains elevated because prices are still higher than they were a year ago.
Inflation rate = [(CPI this period − CPI comparison period)
÷ CPI comparison period] × 100%A CPI is an index, not a price list for every household. In Singapore, the Department of Statistics describes CPI as measuring average price changes in a fixed basket of consumption goods and services commonly purchased by resident households. It explicitly measures price movements, not the absolute price level at one point in time.
Why your personal inflation rate may be different
A national CPI represents an average pattern of expenditure. A household that spends a large share of its budget on rent, childcare, public transport or healthcare may experience a different change in living costs from a household that spends more on other categories. Income, household size, lifestyle, location and purchasing choices all affect the experience.
For example, if food prices rise faster than other categories, a household that spends a large share on food may feel more pressure than the average index suggests. Another household may be affected more by transport or housing-related costs. The CPI remains useful for measuring average price movements, but it is not a personalised household budget calculator.
What causes inflation?
Demand-pull inflation
Demand-pull inflation can occur when total spending in an economy grows faster than the economy’s ability to supply goods and services. If households, businesses or governments compete for limited capacity, businesses may raise prices. Demand can increase because of income growth, credit expansion, government spending, investment or changes in confidence.
Cost-push inflation
Cost-push inflation occurs when production costs rise and businesses pass some of those costs to customers. Examples include higher energy, raw-material, transport, rent or labour costs. The extent of pass-through depends on competition, contracts, demand and businesses’ ability to absorb costs through lower margins or efficiency improvements.
Imported inflation
A country that imports fuel, food, machinery or other goods may experience inflation when global prices rise or its currency weakens against suppliers’ currencies. Exchange-rate changes can affect import costs, although the effect on consumer prices may be delayed or partly absorbed by firms.
Expectations and wage-price dynamics
If households and businesses expect prices to rise, they may change spending, wage negotiations and price-setting decisions. Expectations can influence actual inflation, especially when price and wage adjustments reinforce one another. The relationship is complex and varies with labour-market conditions, productivity and monetary policy.
Inflation versus deflation and disinflation
- Inflation: the general price level rises over time; the inflation rate is positive.
- Disinflation: prices are still rising on average, but the rate of increase is slowing.
- Deflation: the general price level falls over time; the inflation rate is negative.
Suppose a basket costs $100 in one year and $103 in the next. Inflation over that period is 3%. If the basket then costs $104.03 the following year, inflation has slowed to 1% even though the basket costs more than before. That is disinflation, not deflation.
This distinction explains a common frustration: news reports may say inflation has fallen, while shoppers still see high prices. A lower inflation rate means prices are rising more slowly; it does not mean they have fallen back to the old level.
What is the Consumer Price Index (CPI)?
The CPI is a statistical measure of changes in the prices of a defined basket of consumer goods and services. It is widely used to track consumer inflation. The basket, item coverage and weights are updated periodically to reflect changing patterns of household spending. The CPI does not measure every cost experienced by every person and may exclude purchases treated as assets or investment rather than consumption.
Singapore’s CPI is rebased periodically. The current 2024-based basket uses household expenditure information and includes thousands of goods and services collected from a wide range of outlets. The Department of Statistics explains the basket, weights, sampling and why individual households may experience inflation differently. It also notes that the CPI measures price changes rather than absolute prices.
See the official Singapore Department of Statistics: CPI — Our Data Explained.
How inflation affects households
- Purchasing power: if income does not keep pace with prices, the same salary buys less.
- Savings: cash savings lose purchasing power when inflation exceeds the interest earned, although the outcome depends on the account rate and period.
- Debt: fixed nominal repayments may become lighter in real terms if incomes rise with prices, but variable interest rates and stagnant income can make debt harder to manage.
- Budgets: households may need to change brands, quantities, transport choices or discretionary spending.
- Retirement: long retirement plans must consider the possibility that living costs rise over many years.
How inflation affects businesses
Businesses face changing costs for wages, rent, electricity, shipping, components and financing. Some may pass higher costs to customers; others may accept lower margins, redesign products, improve productivity or negotiate with suppliers. Inflation can make budgeting and long-term contracts more difficult because the future purchasing power of a dollar becomes less certain.
For a company, it is important to distinguish nominal revenue growth from real growth. Sales revenue can rise because the business sells more units, charges higher prices or both. Adjusting for price changes helps show whether the business is actually producing or selling more in real terms.
What central banks do about inflation
Central banks can influence economy-wide financial conditions through monetary policy. In many economies, interest rates are a key tool: higher rates can reduce borrowing and spending pressure, while lower rates can support demand. Monetary policy works with lags and cannot directly produce more food, oil, housing or skilled labour. The response depends on whether inflation is driven mainly by demand, supply, expectations or a combination.
Singapore’s monetary-policy framework is different from the interest-rate-targeting approach used by many central banks. The Monetary Authority of Singapore manages the Singapore dollar nominal effective exchange rate within a policy band. This is one reason readers should not assume that every country’s inflation response works in the same way.
How to respond to inflation in a household budget
- Track your own spending: record the categories that actually take the largest share of your budget.
- Separate price increases from higher usage: compare the same quantity, quality and frequency before deciding how much a bill has risen.
- Review recurring costs: check subscriptions, insurance, phone plans and energy use without cutting essential protection blindly.
- Compare suitable alternatives: compare quality, quantity, unit price and total cost, not just the shelf price.
- Protect a cash buffer: plan for essential expenses and irregular bills, while considering the interest earned on accessible savings.
- Review income and commitments: consider whether your income, debt payments and future expenses remain manageable.
Common inflation misunderstandings
- ‘One product became expensive, so inflation is high.’ Inflation concerns a broad general price level, not one isolated price.
- ‘Inflation fell, so prices fell.’ Lower inflation usually means prices rise more slowly; deflation means the overall price level falls.
- ‘CPI is exactly what my family spends.’ CPI is an average basket; personal spending patterns differ.
- ‘Every price rises at the same rate.’ Price changes vary by product, service, region and time.
- ‘A pay rise always beats inflation.’ Compare the percentage increase in income with the relevant change in living costs and taxes or deductions.
Frequently asked questions about inflation
What is inflation in simple words?
Inflation is a sustained rise in the general price level, which means money usually buys less than before.
What is the difference between inflation and disinflation?
Inflation means prices are rising. Disinflation means they are still rising but at a slower rate.
What is the difference between inflation and deflation?
Inflation is a general rise in prices; deflation is a general fall in prices.
Does lower inflation mean groceries are cheaper?
Not necessarily. It means the average rate of price increase has slowed. Individual grocery prices may still be higher than before.
Why does my household feel more inflation than the official CPI?
Your spending weights may differ from the average basket. The categories you buy most may have risen faster than the overall CPI.
Does inflation affect savings?
Yes. When prices rise, a given amount of money buys less. The real return on savings depends on the interest earned relative to inflation.
Continue learning at eduKateSG
To understand how markets influence prices, read What Is Supply and Demand?. For the cross-border costs that can influence imported prices, continue with What Is a Tariff?.
Sources and further reading
The Singapore Department of Statistics CPI guide explains the basket, weights and interpretation of inflation. The latest CPI data page provides official releases. The Federal Reserve’s inflation explainer provides a plain-language description of the general price level. This article is educational; use the latest official release when quoting a current inflation rate.