In econometrics, it is always “payback time”. If advertising has anything close to a science, this is it. It is where clients go to know whether campaigns have increased sales and grown the value of their brands - not how many trophies they picked up at creative jamborees in the south of France.

Ad agency DDB and its specialist unit, DDB Matrix, has been operating at the top of its game recently. It was judged the joint Effectiveness Agency of the Year (above £100m) by the IPA for its work for Volkswagen Diesel, The Guardian and milk brand Cravendale.