User/business value is a relative score from about 1 to 10. Leffingwell suggested using the Fibonacci sequence (1, 2, 3, 5, 8, 13, 21, 34, etc.) mostly because larger numbers are less precise and using Fibonacci makes consensus easier.
see also https://techbeacon.com/app-dev-testing/prioritize-your-backlog-use-weighted-shortest-job-first-wsjf-improved-roi
Having the option to edit the WSJF scale will help with the calculation as the number 34 is missed (40 is used instead).