Trees like the one below are a great way to communicate a formula or a business model. It shows how factors are related. It forces you to "fill in the blanks". For example, if you think you are going to get 200,000 customers in Luxembourg, you need to relate that to the overall population somehow. It makes assumptions very visible, and separates the ones which are relatively certain, from those which are wild guesses.
Use the tree to triangulate your own view of a business model or forecast, then show it to your audience and convince them of the numbers.
I always make my trees left-to-right, McKinsey style, where you would take someone from the big picture to the smaller details. Some clients have a preference for doing it the other way around, going from inputs to the final result.
Feel free to borrow this design idea, or download the ready-made slide from the SlideMagic template store.