[ruds]

The monetary number is not made up out of whole cloth. It's the difference between the book value of the tangible assets of a company as an accountant understands them, and the amount paid for the company. An income stream arising from the operations of a business doesn't count as a tangible asset.

You can absolutely assign a value to that stream. That's how you arrived at the purchase price in the first place! But that income hasn't been realized yet and it's not written in stone. The income could be higher or lower depending on what happens in the future.