The Customer Average Interruption Frequency Index (CAIFI) is a popular

reliability index Reliability index is an attempt to quantitatively assess the reliability of a system using a single numerical value. The set of reliability indices varies depending on the field of engineering, multiple different indices may be used to characterize ...

used in the

reliability analysis Reliability, reliable, or unreliable may refer to: Science, technology, and mathematics Computing * Data reliability (disambiguation), a property of some disk arrays in computer storage * High availability * Reliability (computer networking), a ...

of an

electric power system An electric power system is a network of electrical components deployed to supply, transfer, and use electric power. An example of a power system is the electrical grid that provides power to homes and industries within an extended area. The e ...

.Power Distribution Planning Reference Book, H. Lee Willis, published by CRC Press, 2004, page 112
/ref> It is designed to show trends in customers interrupted and helps to show the number of customers affected out of the whole customer base.

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References

{{Reliability indices Electric power Reliability indices