No, this receipt from 2004 does not prove that prices have tripled in twenty years

Certain insignificant objects sometimes become symbolic. This is the case of this receipt shared by a user of the social network X, on December 21. Presented as a 2004 ticket from the Lidl brand, it shows a total purchase amount of less than 57 euros for around sixty items. “Watch the prices in 2004, it’s crazy,” comments @AkyBeauf, the account that published the image.

The message generated more than 50,000 interactions and was viewed nearly 10 million times, before being taken up by other accounts and being republished on other networks such as Instagram, Facebook or Reddit.

Shortcrust pastry for 1 euro; as much for a bag of grated Emmental; 50 cents for 440 grams of mustard; 69 cents for sweetened yogurt; 85 cents per 1 liter bottle of sunflower oil: all these examples show prices that appear low, looking at 2024.

From 57 to 150 euros for the same basket?

An Internet user decided to start a comparison. “I was bored so I had fun reproducing this shopping list on Leclerc’s drive,” explains the message from @Ke_ziiah, also seen several million times. Results of the operation (the details of which are not known regarding the composition of the basket): 150 euros.

“Times 3 in 20 years, basically the price of races doubles every 10 years,” summarizes one comment. “200% inflation in 20 years”, underlines another. Between 57 and 150 euros, we would indeed approach a tripling. What leads us to conclude that the price of groceries has tripled in twenty years?

Food products 53% more expensive than twenty years ago

To go a little further than a single receipt, we can turn to the consumer price index calculated by the National Institute of Statistics and Economic Studies (Insee). According to this public inflation monitoring tool in France, the prices of all products increased by 39% between 2004 and 2024.

This increase is much more marked for food products: their prices have increased by half (53%) in twenty years, or a multiplication by 1.5. “I would like to see how INSEE does its calculation,” replies a message, under the photo of the receipt, to an Internet user who refers to these INSEE figures. To see more clearly, we asked them. Four reasons make the price index a more reliable measure than the old receipt.

• 1 Do not limit yourself to a specific brand

  “With a price index, what we measure is the evolution of prices,” explains Aurélien Daubaire, head of the consumer prices department at INSEE. “In a sample of 99 urban areas and in overseas departments, we record the price of each type of product in different forms of sale.” Three different sources are used: checkout data, transmitted by supermarkets; physical surveys in convenience stores or markets; price statements on the Internet.

  These readings are therefore carried out “at a very fine level – the price of mustard in a given supermarket – then we calculate the average price”, explains the statistician. This method makes it possible to compare price increases between products and between product categories. Thus, “the price index is representative of all territories and all forms of sales, in proportion to the weight of each territory and each form of sale”. Which is, obviously, not the case for a single ticket from a single brand.

• 2 Use a comparable basket over time

  Another limitation: the differences between the products considered. “The 2004 receipt, projected in 2024, whether based on perception or the INSEE figures, shows an increase in prices in euros over twenty years,” notes Aurélien Daubaire. On the other hand, this receipt does not necessarily allow you to “exactly compare the products”. The case of Lidl, in this respect, is particularly striking: the brand has moved upmarket over the years. So 2004 prices were not only cheaper; they also concerned products offered which are no longer necessarily the same.

  “A given brand, a point of sale, can evolve in the range of products offered, its suppliers, or even the type of households who come to consume there,” confirms Aurélien Daubaire. “Each month, we record the price of the same product at the same point of sale, throughout the year, to eliminate these “point of sale” effects of product range levels.” This method aims to “truly measure the evolution of the price itself”, outside of brand strategies.

• 3 Take consumption habits into account

  Furthermore, are you buying the same thing as in 2004? Yes, we will answer, thinking of basic food products. No, however, for fans of “drive” or shopping in new stores. “Households, commerce and lifestyles are changing,” underlines Aurélien Daubaire. “Around twenty years ago, Internet consumption was much less widespread for a whole series of products. »

  To take these changes into account, INSEE redefines, each year, the basket used to analyze prices. The shopping list is based on actual household consumption. In 2024, for food, the basket includes more than 80 specific products (bread, butter, olive oil, sugar, yogurt, ready meals, frozen products, etc.). The weight of these products is then adapted according to their place in usual consumption.

• 4 Don’t forget the psychological effect

  Like any statistical indicator, this index is based on very real ingredients and observations. “When there is a 20% surge in food prices, this is seen in the price index as well as in the perception,” underlines Aurélien Daubaire. And like any statistical indicator, it happens that our personal perception deviates from it, despite everything. “These are things that we see with certain qualitative surveys,” notes the statistician. “There are periods when there are disconnects” between the price index and consumers’ perception of inflation. The psychological effect of certain products weighs heavily.

  “The price increases for everyday products are particularly notable, and more the increases than the decreases: we receive the reductions but, obviously, we are marked or even in difficulty because of the increases.” The average 53% increase thus hides stratospheric price increases, in comparison. Butter, fresh fish, kilo of beef and potatoes show much more marked increases, sometimes close to a doubling in twenty years. Aurélien Daubaire thus points to “a distorting mirror” represented by these familiar products.

“Everyday products such as refueling, food, oil, butter are particularly striking.” On the other hand, “there are expenses that weigh heavily on household budgets and the increases are perhaps less significant”. And remember that energy prices have increased much more, again, partly explaining the increase in food prices.