Quantitative metrics are numerical indicators that provide insight into how a change has impacted your performance, productivity, quality, or efficiency. These metrics are often based on data that can be collected and analyzed before and after the change, such as time, cost, revenue, defects, errors, or customer satisfaction. Quantitative metrics allow you to compare your results with your goals, benchmarks, or standards and identify areas for improvement or adjustment. For example, return on investment (ROI) is the ratio of the net benefit of the change to the cost of the change; cycle time is the duration of a process or task from start to finish; error rate is the percentage of errors or defects in a product, service, or process; and net promoter score (NPS) is a measure of customer loyalty and satisfaction based on how likely they are to recommend your product, service, or company.