Any idea how to measure a county NEEDs in advance?
Ideal but next to impossible in practice, not to mention it will be manipulated
It is not per county. It is what it takes to deliver a certain service. For example if you devolve education fully, then you know how much would be spent on teachers per county based on the schools and the teachers thereof. That means counties may have to come up with a new method of funding where money follows the student. If 400 Siaya students go to Nandi, then the cost (which would be standardized) would be paid out to Nandi minus that of the 20 Nandi resident students who went to attend schools in Siaya.