What is inflation?

Broad increase in prices

In a market economy, prices for goods and services can always change. Some prices rise; some prices fall. Inflation occurs when there is a broad increase in the prices of goods and services, not just of individual items; it means, you can buy less for €1 today than you could yesterday. In other words, inflation reduces the value of the currency over time.

Some price changes are more important than others

When calculating the average increase in prices, the prices of products we spend more on – such as electricity – are given a greater weight than the prices of products we spend less on – for example, sugar or postage stamps.

Different people buy different things

Every household has different spending habits: some have a car and eat meat, others travel solely by public transport or are vegetarian. The average spending habits of all households together determine how much weight the different products and services have in the measurement of inflation.

For measuring inflation, all goods and services that households consume are taken into account, including:

• everyday items (such as food, newspapers and petrol)
• durable goods (such as clothing, PCs and washing machines)
• services (such as hairdressing, insurance and rented housing)

Compare the price of the shopping basket from year to year

All the goods and services consumed by households during the year are represented by a “basket” of items. Every product in this basket has a price, which can change over time. The annual rate of inflation is the price of the total basket in a given month compared with its price in the same month one year previously.

Euro area inflation

In the euro area, consumer price inflation is measured by the “Harmonised Index of Consumer Prices”, often referred to by its acronym of “HICP”. The term “harmonised” denotes the fact that all the countries in the European Union follow the same methodology. This ensures that the data for one country can be compared with the data for another.

This measure is a good way of keeping track of how prices change in the economy. It is like a map that helps us at the ECB to make the right decisions.

Our job is to maintain price stability. We do this by making sure that inflation – the rate at which the prices change over time – remains low, stable and predictable: 2% over the medium term.

Comparable across countries

Before the euro became our common currency, each country measured inflation using its own national methods and procedures. The introduction of the euro made it necessary to have a means of measuring inflation for the entire euro area, without gaps or overlaps and in a way that could be compared across countries. The HICP, supported by a set of legally binding standards, does precisely this.

Weight of products in the HICP

The impact of a single price change on the HICP depends on how much households spend, on average, on that product.

Example coffee: coffee (together with tea and cocoa) has a weight of 0.4%. So, any change in its price will not have a big impact on the overall HICP.

Example petrol: petrol (together with other car fuels and lubricants) has a weight of 4.6%, meaning that the same percentage price change as for coffee will have an impact about ten times greater on the HICP.

How is the HICP calculated?

1. Collecting prices – Every month, millions of prices are collected in shops and online thanks to automated web-scraping, cash desk scanners, and surveys. These prices cover the whole euro area and are grouped into up to 295 product categories. The exact number of items sampled differs from country to country. For each product, several prices are collected from different outlets and in different regions. Example: book prices take account of various categories of books (fiction, non-fiction, reference, etc.) sold in book shops, supermarkets and by internet suppliers.
2. Weighting product groups – Product groups are weighted according to their importance in average household budgets. To make sure the index remains relevant and reflects changing spending patterns, the weights are updated regularly. They are calculated based on the results of surveys in which households are asked to record what they spend their money on. The weights are national averages that reflect the expenditure of all types of consumer (rich and poor, young and old, etc.).
3. Weighting countries – Countries are weighted according to their share in total euro area consumption expenditure.

Following the 2021 Strategy Review, the Governing Council decided to support the inclusion of home-ownership costs in the HICP to better reflect people’s experiences of rising prices.

Implementing this will take time. Eurostat is working on including owner-occupied housing costs in the HICP.

Until then, we at the ECB will use other measures of inflation that reflect home-ownership costs to improve our understanding of how prices are changing in the economy.

Who calculates the HICP ...

… in the countries? Each euro area country has a national statistical institute. The institute calculates the HICP for its country.

… for the euro area? Each national statistical institute sends its figures to Eurostat, the Statistical Office of the European Communities. Eurostat then calculates the HICP for the euro area as a whole. Eurostat also ensures the quality of the national figures by monitoring compliance with the legally binding standards. For details, see Eurostat.

Perceived inflation

Consumer surveys often show that people “feel” inflation to be higher than the actual price indices indicate. So what forms people’s perceptions of inflation? A number of academic studies have found the following:

• Price rises catch our attention more than stable or declining prices – Increases in prices also stay in our memory for longer. We tend to notice stable or declining prices less, although these prices also count when calculating the average inflation rate.
• We notice frequent, out-of-pocket purchases more – In recent years, the prices of some goods and services we buy frequently have increased above average. Examples of these are petrol, bread and bus tickets. We often pay too much attention to changes in the prices of these items when thinking about inflation. This may mean we end up overestimating the actual rate of inflation.
• We notice infrequent purchases and direct debits less – A substantial amount of our household budget is spent on goods and services that we buy less frequently. Examples are cars and holidays. There are also items we often pay for by automatic bank transfer (direct debits and standing orders), such as rented housing and telephone bills. We tend to notice these expenditures and changes in their prices less when thinking about inflation.

• “Personal” inflation – The Harmonised Index of Consumer Prices (HICP) is based on an average basket of goods and services. This average basket is representative for all households. However, households that experience an above-average inflation may be more acutely aware of this than those that benefit from a below-average inflation.

  Example: if petrol prices increase much more than the prices of other goods and services, people who use a car frequently may “feel” a rate of inflation that exceeds the HICP because their personal expenditure on petrol is higher than average. By contrast, those who use a car rarely or not at all will experience a lower “personal” rate of inflation.

• Inflation rates are annual, but our memory goes back further – The HICP is usually reported as an annual growth rate. This means that the general price level for a particular period of time – say, January 2009 – is compared with the same period one year earlier – namely January 2008. When forming their perceptions, people may think back to prices several years ago. Over a long period of time prices tend to rise substantially, even with a low annual rate of inflation. For example, if the annual rate of change of the HICP is 2%, after 10 years the general price level will have increased by over 20%.

• Price changes versus quality changes – We often consider changes in a product’s price tag as inflation. But sometimes the quality of the product changes at the same time. The HICP deals with this by subtracting the change that is due to quality.

  Example: car prices may have gone up but new models often include, as standard, features that were previously sold as optional extras (for example, satellite navigation systems, air conditioning and airbags). In such cases, the price increase is due partly to an increase in quality and not only to inflation. If car prices went up, say, 5% on average but quality increases accounted for 1%, then the HICP would reflect a 4% increase for this product.

Explore data

Consumer price inflation in the euro area since 1961

In the 1970s and 1980s inflation was high in many European countries. But since the mid-1990s, inflation rates have been markedly lower thanks to countries preparing for the launch of the euro and to the monetary policy of the ECB.

Very recently, inflation rates have increased significantly, mainly because of surging energy and food prices.

What is driving the latest inflation rate?

It’s not always the items whose prices change the most that have the biggest impact on the index. The rate of inflation also depends on the share of each product in average household consumption expenditure – in other words a product’s “weight”.

Explore the latest data with this interactive inflation dashboard

Check out the latest data and historical data. Take a look at individual countries and drill down into individual product groups. When you select a timeline, the development of inflation over time will be shown in an animation, month after month.