Net Promoter Score (NPS) is a popular method of measuring customer satisfaction when analysing feedback provided on a 1 to 10 scale.

An NPS result returns anything between 100 and -100 so it can be a useful mechanism for converting customer feedback scored on a 1-10 basis into a percentage, whilst at the same time eliminating ‘passive’ feedback where the customer is neither overly positive or negative in their response.

Responses of 9 or 10 are ‘promoters’, considered to represent customers who will happily endorse your products. Responses between 0 and 6 are ‘detractors’ who are unlikely to endorse you and finally answers between 7 and 8 are classed as ‘passives’ representing customers who don’t appear to have strong views in either direction.

Here is some dummy date from a customer satisfaction survey scored on a 1-10 scale, where 1 is scored as the least satisfied and 10 the most satisfied.

In the example dataset there are 10 promoters, 3 passives and 3 detractors. A formula to calculate NPS on the values in column C is *=100*(COUNTIF(C:C,”>=8″)-COUNTIF(C:C,”<7″))/COUNT(C:C)* returning an NPS of 43.75. An alternative method of calculating NPS, which is perhaps simpler to remember, is the % of promoters minus the % of detractors. In this case 10 of 16 were promoters (62.5%), 3 of 16 were detractors (18.75%) so 62.5% – 18.75% = 43.75%.