There is a conundrum in the advertising industry, like Goldbach’s Conjecture, which was posed by the famous advertising guru John Wanamaker: I know that half of my advertising spends are wasted, but unfortunately, I don’t know which half are wasted.

This question has been troubling all advertising practitioners ever since it was raised.

Advertising means investment of money, and input is inevitably associated with output.

What the entrepreneur cares about is whether the investment of money will produce a corresponding return!

But in any case, most entrepreneurs expect to invest one dollar in return for three, five or even more

Hoping to turn the overwhelming advertising into a kind of precise target advertising, so as to achieve the purpose of “eliminating one enemy with each bullet”, only in this way can the advertising money be “spent on the point of use”.

Numerous advertisers have been searching for it: what wasted “half of the advertising money”?

After nearly a century of puzzling, no one has found an answer, but one person has found a conversion formula that comes the closest to that answer.