Customer Average Interruption Duration Index (CAIDI) KPI

Customer Average Interruption Duration Index (CAIDI) is a critical performance indicator that measures the average time customers experience service interruptions.

This metric directly influences operational efficiency and customer satisfaction, as prolonged interruptions can lead to dissatisfaction and churn.

By tracking CAIDI, organizations can identify areas for improvement, enhance service reliability, and ultimately drive better business outcomes.

A lower CAIDI indicates effective response strategies and robust infrastructure, while a higher CAIDI may signal underlying issues in service delivery.

Companies that prioritize CAIDI often see improved financial health and stronger customer loyalty.

How Customer Average Interruption Duration Index (CAIDI) Connects to Your Strategy

This index appears in two KPI groups. In Electric Transmission & Distribution Utilities it ranks third, behind only system average interruption duration index and system average interruption frequency index. In Electric Power it ranks seventh, below the generation and availability metrics that lead that group: capacity factor, energy availability factor, forced outage rate, planned outage rate, and the two system indices. So the same metric is a near headline reliability measure in the transmission and distribution group and a supporting one in the broader power group.

Its balanced scorecard placement is the customer perspective, which sets it apart from its closest neighbors. System average interruption duration index and system average interruption frequency index both sit in the internal perspective; this index reframes the same outage data around what one affected customer experiences per interruption. Read it as a lagging, outcome oriented measure: it reports the restoration experience after outages have already happened, so it confirms how well crews and processes performed rather than forecasting the next event.

The sharpest tension is with system average interruption frequency index, which ranks just above it in the transmission and distribution group. This index is defined as duration per interruption, so it moves inversely with frequency in a way that can mislead. When a utility clears many short interruptions, frequency falls, but the remaining events are the longer, harder ones, and the average restoration time per interruption can rise even though customers are collectively better off. A crew genuinely improving reliability can watch this number worsen, so it should never be read alone. Its companion tension is with system average interruption duration index: total customer minutes can fall while this per interruption average climbs, and only reading both together tells the real story.

Measuring Customer Average Interruption Duration Index (CAIDI) in Practice

The underlying data comes from the outage management system: each interruption event with its start and restoration timestamps and the count of customers affected. Because the formula divides total outage minutes by the total number of customer interruptions, the honest join is at the interruption level, not the customer minute level, and mixing the two is the fastest way to produce a wrong figure. Align the outage log with the customer count of record for the same period so that the numerator and denominator describe the same events.

The forks to settle before measuring are mostly about scope. Decide which events count: whether major event days from severe weather are included or excluded, since a single storm can swamp the average and a utility that quietly drops storm days is not comparable to one that keeps them. Decide the momentary interruption threshold, because whether brief blips count as interruptions changes the denominator and therefore the whole index. Decide the reporting period, since a metric that folds in a storm season reads very differently from a calm quarter.

Segmentation that matters here is by feeder, by region, and by cause, because restoration time is driven by crew access and terrain more than by any single system average. The instrumentation pitfall unique to this index is its inverse relationship with frequency: improving frequency by resolving small interruptions can push this average up, so always report it beside frequency and duration rather than in isolation, and never treat a rise as automatic evidence of worse service.

Common Pitfalls

Many organizations overlook the importance of CAIDI, focusing instead on other metrics that may not fully capture customer experience.

• Failing to invest in infrastructure upgrades can lead to increased service interruptions. Aging systems often struggle to meet demand, resulting in longer recovery times during outages.
• Neglecting to analyze root causes of interruptions prevents organizations from addressing systemic issues. Without this analysis, similar problems are likely to recur, eroding customer trust.
• Inadequate training for response teams can result in inefficient incident management. Teams lacking proper skills may take longer to resolve issues, negatively impacting CAIDI.
• Ignoring customer feedback on service interruptions can lead to missed opportunities for improvement. Engaging customers in discussions about their experiences can yield valuable insights for operational enhancements.

Improvement Levers

Enhancing CAIDI requires a strategic focus on both technology and personnel.

• Invest in advanced monitoring systems to detect outages early. Real-time alerts can enable quicker response times, minimizing customer impact during incidents.
• Implement regular training programs for response teams to ensure they are equipped with the latest best practices. Continuous education fosters a culture of excellence in service recovery.
• Conduct thorough root-cause analyses after service interruptions to identify and rectify underlying issues. This proactive approach can prevent future occurrences and improve overall service reliability.
• Enhance communication with customers during outages to manage expectations effectively. Keeping customers informed can mitigate frustration and improve their overall experience.

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OKRs That Use Customer Average Interruption Duration Index (CAIDI)

In the Electric Transmission & Distribution Utilities group this index ladders to the objective improve customer satisfaction by reducing interruptions and optimizing service interactions, where it already appears as a customer facing key result alongside the customer satisfaction index and customer service response time. Frame it directionally: shorten average restoration time per interruption toward a target the team sets, and hold it next to frequency so the team does not book an apparent gain that is really the arithmetic of fewer small outages.

A second framing comes from the Electric Power group and its objective enhance grid resilience against natural disasters to reduce outage impacts, where this index sits with grid resilience to natural disasters and load factor. Here it works as an after event measure of how quickly service is restored once a disaster hits, so treat it as a confirming key result on resilience investments rather than the primary lever. The group best practice is explicit about tying customer satisfaction improvements to interruption indices and service responsiveness, which is exactly the role this metric plays.

See OKR Examples for Electric Transmission & Distribution Utilities

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KPI Categories

This KPI is associated with the following categories and industries in our KPI database: