
Strategy & Craft
Splitting an ad budget: the 70-20-10 rule
Seventy per cent on what works, twenty on scaling, ten on experiments. The rule is old, simple, and violated in almost every account.
Strategy & Craft
Age, income and interests describe a category, not a customer. Three better questions produce a definition you can actually target.

The standard audience definition looks like this: "Men and women, 35 to 55, above-average income, interested in home and garden." That describes roughly twenty million people and helps with nothing.
Two people of the same age, income and postcode buy completely differently depending on one thing: whether something has happened to them.
Nobody buys a heat pump because they are 47. They buy it because the boiler failed, or the house was inherited, or a grant deadline is approaching. The trigger is the audience definition; the demographics are decoration.
1. What happened just before? The event that started the search. A move, a failure, a birth, a regulation, a competitor's price rise, a bad experience elsewhere.
2. What are they doing instead right now? Not "nothing". They are using a competitor, patching the problem themselves, or postponing. Your advertising competes with that, not with an abstraction.
3. What would stop them buying? Price, lead time, disruption, doubt about competence, a decision-maker who must agree. Those objections are your copy.
Before commissioning research, read what you already have.
| Source | What it reveals |
|---|---|
| Last 50 invoices | who actually buys, by size and type |
| Enquiry emails | the words customers use for the problem |
| Sales call notes | the objections that recur |
| Search terms in your own site search | what people expect you to have |
| Reviews, yours and competitors' | what pleases and what infuriates |
The second row is the highest-value and lowest-effort. Copy fifty enquiry emails into one document and read them in one sitting. The recurring phrases are your headlines.
A usable audience definition fits in three lines and reads like a person.
"Owners of houses built before 1990 in the district, whose gas boiler is over 15 years old, who have heard about the grant scheme but do not know whether they qualify, and who fear the work will take weeks."
That definition tells you the message, the channel, the objection to handle and the season to run it. The demographic version told you nothing.
Split into two audiences only when the message must genuinely differ. Same message, different age, is one audience. Different reason to buy, different objection, is two.
One per campaign. Serving three audiences with one message produces a message for none of them.
Only if built from real interviews. Invented personas encode the team's assumptions and then protect them from challenge.
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