What is a crucial assumption made when calculating loss development factors?

The crucial assumption made when calculating loss development factors is that current losses will follow the same payment pattern as past losses. This means that actuaries and analysts rely on historical data to project how current claims will be paid out over time. By assuming that the future payment behavior of losses will mirror that of past losses, the calculation allows for estimating the ultimate cost and timing of claims.

This assumption is grounded in the principle that, while the external factors affecting claims may change, the basic patterns of claims development—such as the speed and timing of payments—tend to remain relatively consistent. This provides a framework for predicting future claims costs based on established trends. Accurate loss development factors are essential for effective reserving and underwriting practices within insurance operations.