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Exceedance probability

Probability that a loss exceeds a given threshold over a one-year period, the central curve in catastrophe modeling.

Definition

Exceedance probability (EP) is the probability that an annual loss exceeds a given level. The EP curve is the central tool in catastrophe modeling and XL layer pricing. OEP (occurrence EP: probability that the largest single event of the year exceeds the threshold) and AEP (aggregate EP: probability that the annual sum of losses exceeds the threshold) are distinguished. The 1% exceedance probability corresponds to the 100-year return period, the reference metric in catastrophe cover discussions. The horizontal axis of an EP curve gives the loss amount, the vertical axis the probability.

Example

European windstorm OEP curve: 1% probability loss (100-year return period) = 450 M EUR. This figure serves as the reference for sizing the cat XL reinsurance program.

Related terms
Also known as

exceedance probability, AEP, OEP, probabilité d'excédement, annual exceedance probability