Proving the value of CRO for top level management

You used to put all of your time and effort into building those AB-tests and creating great analysis of them. Now the board asks you to show them the value of your company working with CRO. How do you answer that, and what numbers do you show this new group of people? I will show you how I have approached this situation and what actually worked. But even more exciting – what numbers does not seem to work for top management at all.