The actual metrics and measurements that indicate whether you are meeting your Service Level Objective (SLO). Most SLIs are measured in percentages to express the service level delivered. For example, if your SLO is to deliver 99.5% availability, the actual measurement may be 99.8%, which means you’re meeting your agreements and you have happy customers. To gain an understanding of long-term trends, you can visually represent SLIs in a histogram that shows actual performance in the overall context of your SLOs.