Right, they would have to define their parameters first, and there might be a margin of error. But then, that's true of every revenue number they track. And thi

Right, they would have to define their parameters first, and there might be a margin of error. But then, that's true of every revenue number they track. And this probably is one of the most important sources of revenue they have. So, I just try unsuccessfully to imagine a scenario where an executive says "I guess we'll never know if revenue is going up or down, c'est la vie!"