fuelEfficiency

The distance traveled per unit of fuel used; most commonly miles per gallon (mpg) or kilometers per liter (km/L).\n\n* Note 1: There are unfortunately no standard unit codes for miles per gallon or kilometers per liter. Use unitText to indicate the unit of measurement, e.g. mpg or km/L.\n* Note 2: There are two ways of indicating the fuel consumption, fuelConsumption (e.g. 8 liters per 100 km) and fuelEfficiency (e.g. 30 miles per gallon). They are reciprocal.\n* Note 3: Often, the absolute value is useful only when related to driving speed ("at 80 km/h") or usage pattern ("city traffic"). You can use valueReference to link the value for the fuel economy to another value.