public Duration scalingDuration() {
        int completedEventCount = 0;
        Duration totalDuration = Duration.ZERO;
        for (ScalingEvent event : scalingEvents()) {
            if (event.duration().isEmpty()) continue;
            // Assume we have missed timely recording completion if it is longer than 4 days, so ignore
            if ( ! event.duration().get().minus(Duration.ofDays(4)).isNegative()) continue;

            completedEventCount++;
            totalDuration = totalDuration.plus(event.duration().get());
        }
        if (completedEventCount == 0) return ClusterModel.minScalingDuration();
        return minimum(ClusterModel.minScalingDuration(), totalDuration.dividedBy(completedEventCount));
    }
The predicted time it will take to rescale this cluster.
node-repository/src/main/java/com/yahoo/vespa/hosted/provision/applications/Cluster.java