The problem with ratio ratings like you propose is that there is no end. You have to anchor the ratings or they have no grounding in reality. (Produce a few mo

The problem with ratio ratings like you propose is that there is no end. You have to anchor the ratings or they have no grounding in reality. (Produce a few models of bad service and drivers and excellent service and drivers.) That is, unless you really want to chase some sort of unattainable perfection.