 You don't have a choice. It'll depend on what the manufacturer is trying to achieve from emissions values. The reason there's start-stop, let me answer it this way. The reason there's start-stop is manufacturers are trying to hit a certain fuel economy because how many cars they sell that get 40 miles to the gallon versus how many cars they sell that get 20 miles to the gallon, they get emissions credits and different compensation from the government because they're trying to clean up the environment.