Net Promoter Score (NPS) measures the loyalty that exists between a provider and a constumer.
It is calculated based on responses to a single question: "How likely is it that you would recommend our company/product/service to a friend or colleague?" The scoring for this answer is most often based on a 0 to 10 scale.
30 is considered good, over 50 is great, and over 70 is excellent.
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