Zygmore

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Small labs for understanding business.

Small explorations of everyday business problems: useful tools, illustrated cases, discoveries, revisions and open questions. No business or analytics training needed.

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A small experiment

A 10% discount lifts sales by 20%. Revenue goes up. Does the business come out ahead?

See what happens

No. Contribution falls from $1,800 to $1,710. To keep $1,800, sales would need to rise 26.3% — at least 190 whole units instead of 150.

Why, step by step →

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Featured tool · Will your price change pay off?

How many sales does my price change need to pay off?

Enter one product's price, cost and sales. See how many units each discount or increase needs to keep today's contribution. Works on its own — the walkthrough is optional.

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Contribution at 10% off versus units soldA rising line shows contribution at $22.5 per unit: $9.5 per unit times units sold. A dashed line marks today's contribution of $1,800. The rising line crosses it at about 189.47 units. At 180 units, 20% more than today, contribution is $1,710, below today.$1,200$1,400$1,600$1,800$2,000140160180200Units sold in the periodContribution per periodToday: $1,80010% off: units × $9.50hurdle ≈ 189.47+20% units → $1,710
Hypothetical example: $25 price, $13 variable cost, 150 units in a comparable period. Contribution excludes overhead.
Show the numbers as a table
UnitsContribution at 10% offvs today
150$1,425−$375
160$1,520−$280
170$1,615−$185
180$1,710−$90
190$1,805+$5
200$1,900+$100

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