Segment value · The lifetime value · Element
The duration
How long a customer in this segment stays.
The part
What it is
Measured rather than assumed. Retention differs sharply by segment and is the input that most changes the ranking.
For young businesses the honest answer is that duration is unknown, and using an assumption is fine provided it is labelled.
The smallest level
The attributes it carries
Each attribute is one of the framework’s shared types. What a date is, and how it is written, is defined once for the whole model — the note here says what it means in this particular place.