Marketing decisions start with numbers: how big the market is, how fast it grows and how much of it you hold. This page shows you how to calculate those numbers and what they mean.
If a firm's sales go up, why might the examiner still say it is doing badly?
Marketing data tells a business how big its market is, how fast it grows and what share it holds. Students calculate market growth, market share and return on marketing spend, read sales by region, product or store, and judge whether correlation shows cause. The type of market (B2B, B2C or C2C) and the level of competition shape which marketing works.
Year 12 (7137/7138): This is core AS content (the first-year qualification) under 3.1.3 Marketing management. Learn the three formulas exactly, and practise reading data tables. You will meet this content again in A-level Paper 1, and Paper 3 draws on it when judging strategy.
Year 13 (7132, June 2027): You studied market size, growth and share in 7132 section 3.3. Use this page to check your formulas and to practise interpreting sales data. Treat return on marketing spend and C2C markets as extras: they may help your evaluation but are not the core of your course.
The specification asks you to calculate, interpret and analyse marketing data. Market size is total sales of all firms in a market, in value (£) or volume (units). A segment is one part of that market, such as students or families. Segment size is the sales in that part.
Marketing data helps a business set objectives, choose where to compete and judge whether its spending worked. A number alone says little, so always compare it with something: last year, a rival or the whole market.
Illustrative figures: a market was worth £400m last year and £440m this year. Market growth = £40m / £400m x 100 = 10%. A firm sells £55m this year. Its market share = £55m / £440m x 100 = 12.5%.
Illustrative figures: a campaign cost £60,000 and produced £90,000 of profit. Return on marketing spend = £90,000 / £60,000 = 1.5. Each £1 spent returned £1.50 of profit. A result below 1 means the spending did not earn back its cost.
Firms split sales data by region, product or store. This shows where growth or decline is hiding. A rise in total sales can hide one store that is falling fast.
Sales volume is the number of units sold. Sales value is volume x price. Illustrative figures: 10,000 units at £5 gives £50,000. Next year 9,000 units at £6 gives £54,000. Value rose 8% but volume fell 10%, so more customers were lost even though revenue rose.
An index number sets a base year at 100. Index = value / base value x 100. Illustrative figures: sales of £200k (base, index 100), £230k (index 115) and £250k (index 125). The rise from 115 to 125 is 10 index points, but the percentage change is 10 / 115 x 100 = 8.7%. Do not mix up points and percentages.
Correlation describes how two sets of data move together. Positive means both rise together. Negative means one rises as the other falls. Strong means the points sit close to a line. Weak means they are scattered. Correlation does not prove that one thing caused the other.
No named model from Annex 8 (the specification's list of sophisticated concepts) is needed here. The Boston Matrix, which you meet elsewhere, does use market share and market growth, so these skills feed into it.
A B2B market (business to business) sells to other firms. Buyers are few, orders are large and decisions involve several people. So marketing relies on personal selling, relationships and technical detail rather than mass advertising.
A B2C market (business to consumer) sells to individuals. Buyers are many and decide quickly, often on emotion and price. So marketing uses branding, promotion and convenient distribution.
A C2C market (consumer to consumer) is where individuals sell to each other, usually through an online platform. The platform firm does not sell the goods. It markets trust, safety and ease of use, and it earns fees.
Goods are physical and can be stored. Services are intangible and used when produced, so quality varies and you cannot hold stock. Service marketing therefore stresses people, process and reputation, because customers cannot test the product first.
The degree of competition is how many rivals there are and how alike they are. In a crowded market, firms need clear differences or low prices. In a market with few rivals, firms may compete on non-price factors.
Competitive behaviour means how rivals act: price cuts, new products, promotion. A firm must respond or lose share. Market growth matters too. In a growing market, firms can gain sales without taking customers from rivals. In a mature or shrinking market, one firm's gain is another's loss, so competition becomes sharper.
Real data shows this. In Kantar's four weeks to 5 October 2025, UK take-home grocery sales grew 4.1%, while Lidl grew 10.8% and raised its share to 8.2%.[3] Lidl grew far faster than the market, so it took share from rivals.
Firms publish sales growth, share and like-for-like figures. Like-for-like sales compare shops that traded in both periods. They remove the effect of opening new shops, so they show whether existing customers are buying more.
Greggs reported total sales of £2,151m in 2025 against £2,014m in 2024, a rise of 6.8%.[2] Like-for-like sales in company-managed shops rose only 2.4%.[2] The gap tells you that much of the growth came from new shops, not busier old ones.
Market share can move even when sales rise. In Kantar's December 2025 data, Tesco's sales were 4.3% higher and its share rose 0.2 percentage points to 28.7%.[1] Aldi's sales rose 3.9% but its share stayed at 10.1%.[1] Aldi grew, but only in line with the market, so it did not gain share.
Notice the phrase percentage points. A rise from 28.5% to 28.7% is 0.2 percentage points, not 0.2%.
Data helps judgement, but it has limits. Evaluation is about what the figure depends on.
Dividing by the new figure instead of the original when finding growth. Writing market share as a share of the firm's own sales. Calling a rise in share a rise in sales, or the reverse.
Mixing up percentage points and percentages. Treating correlation as proof of cause. Stopping at the number without saying what it means for this business, so you earn AO1 only and miss AO3 and AO4.
Every AQA Business question uses one of five command words, each with a fixed mark tariff, and quantitative questions sit inside the 9 and 15-mark formats. The A-level papers have no 2 or 4-mark questions. Open each format to see how this topic appears in it. All questions here are original Curriculum Circle practice questions, not board questions.
On this topicYou are asked for a precise meaning of a data term, such as market share or a C2C market.
What earns the marksTwo marks for AO1: one for a correct core meaning and one for a precise detail, such as the percentage or the platform role.
CC practice questionDefine the term 'market share'. [2 marks]
On this topicYou explain how a figure or market type affects a firm, in one developed point linked to the business.
What earns the marksAO1 for knowing the term and AO2 for applying it to the named firm in the case.
CC practice questionExplain one way in which selling to other businesses (B2B) rather than to consumers might change the marketing of a firm making industrial cleaning equipment. [4 marks]
On this topicYou build a chain of reasoning from a number to a consequence, such as how a fall in market growth affects competition.
What earns the marksAO1 for the concept, AO2 for the context and AO3 for a developed chain using because and so.
CC practice questionAnalyse how slowing market growth might affect the marketing of Kiln & Co, a chain of 30 coffee shops in northern England. [6 marks]
On this topicYou weigh up what a data set shows, such as whether rising sales prove a marketing campaign worked.
What earns the marksAO1 to AO3 for arguments on both sides, and AO4 for a judgement that says what it depends on.
CC practice questionAssess whether a rise in sales of 12% proves that the new advertising campaign at Kiln & Co was a success. [9 marks]
On this topicYou compare two courses of action using data, such as expanding in one region or raising spend in another, and recommend one.
What earns the marksAO1 to AO4, with the highest credit for a justified recommendation that uses the figures and states its limits.
CC practice questionKiln & Co can open five shops in the North East or spend £150,000 on a loyalty app. Evaluate which option it should choose. [15 marks]
On this topicYou calculate growth, share or return on marketing spend from a table, then use the result to support a judgement.
What earns the marksAO1 for the correct formula and AO2 for using the figures, with AO3 and AO4 for what the result means and how reliable it is.
CC practice questionIllustrative figures: the market was worth £80m in 2025 and £92m in 2026. Kiln & Co sales were £8m in 2025 and £9.2m in 2026. Its campaign cost £400,000 and earned £500,000 of profit. Calculate market growth, market share in 2026 and return on marketing spend, then assess whether the campaign was a success. [9 marks]
| Weight | What it is | What it means on markets and marketing data | |
|---|---|---|---|
| AO1 | 32.5% AS · 24.44% A-level | Knowledge and understanding of terms, concepts, theories, methods and models | Know the three formulas exactly, the meanings of B2B, B2C and C2C, and the terms for correlation and index numbers. |
| AO2 | 27.5% AS · 24.44% A-level | Application to the business context in the case study | Use the case figures and the firm's market type. Name the region, product or store and quote the number. |
| AO3 | 20% AS · 26.66% A-level | Analysis of issues and their impact on individuals and organisations | Link a number to a cause and a consequence, such as slow market growth leading to sharper price competition and lower margins. |
| AO4 | 20% AS · 24.44% A-level | Evaluation of quantitative and qualitative information to make judgements | Judge what the data proves. Weigh time period, market definition and correlation against cause, then reach a conclusion. |
Weightings are approximate and taken from the AQA AS 7137 and A-level 7138 specification [0].
Hearth & Crumb, a fictional bakery chain, can open three shops in a fast-growing region or spend £120,000 on a loyalty app for existing customers. Evaluate which option it should choose. [15 marks]
New shops raise sales volume because the region's market is growing, so the firm can win customers without taking them from rivals. This lifts total sales, so it also lifts market share if the firm grows faster than the market. The app targets existing customers, so it may raise sales per customer and repeat visits, and its return on marketing spend can be measured from loyalty-card data.
The choice depends on the figures. If the new region's market grows faster than the firm's current one and competition there is weak, shops are the stronger choice. If the app's return on marketing spend is above 1 in the pilot, it is cheaper and lower risk. Strong correlation between app use and sales does not prove the app caused the rise, because loyal customers may simply use it more. I would recommend the app first, because it can be measured quickly, then shops once growth data is confirmed.
In Kantar's December 2025 data, Tesco's sales were 4.3% higher than a year earlier and its market share rose 0.2 percentage points to 28.7%.[1] Aldi's sales rose 3.9% while its share stayed at 10.1%.[1]
Greggs reported total sales of £2,151m in 2025, up 6.8% from £2,014m in 2024.[2] Like-for-like sales in company-managed shops grew by 2.4%, so new shops explained much of the growth.[2]
In the four weeks to 5 October 2025, Kantar found UK take-home grocery sales up 4.1%, while Lidl's sales grew 10.8%.[3] Lidl's share rose 0.5 percentage points to 8.2%.[3]
Everything above is the topic page. The pieces below take it further. Each one trains a particular assessment objective rather than covering the topic again, and they are added over the year.
Figures and facts were checked against these sources on 2 November 2026. Worked numbers labelled "Illustrative figures" are invented for teaching.
For more practice with data tables and marked answers, the CC Business revision platform and the Inner Academy's recorded lessons go further.
See the Business platformThe Inner Academy