A Key Performance Indicator (KPI) is a visual cue that communicates the amount of progress made toward a measurable goal. For more about KPIs, see Key Performance Indicators (KPIs) in PowerPivot.
If you are showing an important measure value in the report, and you want to compare it with a target and see if it meets the target or not, The KPI visual comes in handy. The KPI Visual’s behavior, however, might be a bit hard to understand, In this article and video, I explained how this visual works, and how you can use it in your reports.
Read more about it from my blog article here: