What it means
Revenue growth of 20% sounds impressive until you discover the market grew 35%. Market share growth strips out the tide, so you can see whether the company is genuinely taking customers from competitors or simply floating upwards along with everyone else in the industry.
There are two ways to express the change, and confusing them causes more boardroom arguments than almost any other metric. Moving from 6% share to 8% share is a rise of 2 percentage points, or a relative increase of one third.
Reporting "33% share growth" without saying that the figure is relative overstates the achievement to anyone reading quickly. The denominator is the difficult part.
Total market size normally comes from an industry association, a research firm or a bottom-up estimate, and every one of those sources revises its history from time to time. Committing to a single source, disclosing which one it is, and restating prior periods whenever it changes is what keeps the series usable over several years.
Share can be measured in revenue, units or customers, and the three often point in different directions. A company discounting heavily can gain unit share while losing revenue share, which is a warning signal rather than a win.
Boards typically watch revenue share for financial planning and unit share as a read on competitive position. Share growth is also worth splitting by segment and geography, because a flat national figure can conceal a strong gain in one region offset by quiet losses elsewhere.
Sales leaders use those splits to decide where to add headcount, where to defend and where to withdraw.
In practice
Real-world examples.
Example
A pet food brand reports 14% revenue growth and celebrates, until retail scanner data shows the category grew 19% and its share slipped from 4.2% to 4.0%. The board reframes the year as a loss of ground despite record sales.
Example
A regional insurance broker increases share of the local haulage segment from 11% to 15% over two years by hiring three specialist brokers. Because the segment itself was flat, every point of share came directly from named competitors.
Example
A smartphone accessory maker gains unit share from 7% to 9% after cutting prices by a fifth, but its revenue share falls from 8% to 7%. Management concludes the trade was unprofitable and restores prices on the two best-selling lines.
Think of it
“Market share growth shows if you're gaining ground versus competitors-your share increase.
Formula
Calculation
Market share = Company revenue / Total market revenue x 100. Growth in percentage points = current share - prior share. Relative growth = (current share - prior share) / prior share x 100.
In the prior year, a commercial cleaning group generated revenue of $30,000,000 in a market worth $500,000,000, giving a share of 30 / 500 x 100 = 6%. This year it generated $48,000,000 in a market that grew to $600,000,000, giving 48 / 600 x 100 = 8%.
Share growth is 8% - 6% = 2 percentage points, and the relative growth is 2 / 6 x 100 = 33.3%. Behind those figures, company revenue rose from $30,000,000 to $48,000,000, an increase of 60%, while the market itself grew from $500,000,000 to $600,000,000, an increase of 20%. Growing three times as fast as the market is what turned strong revenue growth into a genuine share gain.Case study
Seen in the real world.
Brambleton Beverages is an entirely fictional soft drinks producer used here as an illustrative example. For three years it reported market share growth to its board using data from one research provider, showing a climb from 3.1% to 4.4% of the chilled juice category.
In the fourth year the provider revised its category definition to include chilled smoothies, which expanded the measured market by about a fifth. Brambleton's share dropped to 3.7% overnight without a single lost customer, and a board member reasonably asked whether the previous three years had been real.
The illustrative resolution was straightforward but tedious: the finance team obtained restated history on the new definition and rebuilt the entire series, which showed genuine growth from 2.6% to 3.7% on a consistent basis. The fictional company then adopted a rule that any change of data source or definition must be accompanied by a full restatement before the number reaches the board pack.
Watch out
Common mistakes.
- Quoting relative share growth as though it were percentage points, so that a move from 6% to 8% is described simply as 33% growth with no context.
- Changing the market size source or definition mid-series without restating history, which manufactures growth or decline that never happened.
- Assuming revenue growth and share growth move together, when a company can grow revenue strongly and still lose share in a faster-growing market.
Questions
People also ask.
Should share be measured in revenue or units?
Both are useful, and looking at them together is the point, because divergence between them usually signals a pricing or mix change worth investigating.
How can a company gain share while revenue falls?
If the overall market contracts faster than the company's own sales, share rises even as revenue declines, which is common in a recession.
Is gaining share always worth the cost?
No, because share bought through deep discounting or unprofitable contracts can reduce total profit, so share targets should always sit alongside margin targets.
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