Leading and lagging indicators are two types of measurements used when assessing performance in a business or organisation. A leading indicator is a predictive measurement, for example; the percentage of people wearing safety belts in a vehicle is a leading safety indicator. A lagging indicator is an output measurement, for example; the number of road traffic crashes is a lagging safety indicator.
The difference between the two is a leading indicator can influence change and a lagging indicator can only record what has happened. In the attached document examples are provided for the priority areas in fleet management: cost efficiency, effectiveness, safety and environmental impact.
Some indicators are cross-cutting; meaning that they influence more than one priority area.
This list is not exhaustive but serves to give inspiration about leading and lagging indicators.