The metric is assigned to a KR. It is used to measure whether the owner of an OKR has achieved the key result targeted and the objective. When defining key results or KRs, state them in black and white. In an OKR tool, you may choose a metric based on which you and your contributors will evaluate the OKR progress. The metric of an OKR can be a %, number, currency, a binary yes or no, or no units.
