Net Promoter Score

For question 1, promoters score 9-10, detractors score 0-6. NPS is the percentage of promoters minus the percentage of detractors, rounded to the nearest integer. Return the NPS.

Table schema

Responses(id INT PRIMARY KEY, respondent INT, question INT, score INT)

Sample data

id | respondent | question | score
1 | 1 | 1 | 9
2 | 1 | 2 | 4
3 | 2 | 1 | 7
4 | 2 | 2 | 5
5 | 3 | 1 | 10
6 | 3 | 2 | 5
7 | 4 | 1 | 3