The expected life

How long the asset is expected to serve, set when it is acquired.

The part

What it is

The estimate should come from the technology and the usage rather than from depreciation policy, which answers an accounting question rather than an operational one.

Recording it at acquisition is the whole discipline. Recorded later, it is set to whenever the asset happens to have failed.

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.

Expected life
Set at acquisition, from technology and usage rather than depreciation policy.
Duration shared type
Expected replacement
The date that puts the decision into a budget cycle.
Date shared type
Basis
Why this life, which is what makes it revisable when usage changes.
Reason shared type