A company can measure its performance by asking “how likely is it that you would recommend company X to a friend?” or “how likely is it that you will continue to purchase our products and services?”. Customers respond on a 0-to-10 point rating scale (see image above). Detractors generate negative word-of-mouth, passives are vulnerable to competitive offerings, and promoters generate positive word-of-mouth. Hence, net promoter score (NPS) takes the percentage of promoters and subtracts the percentage of detractors.