definition
strict definition
system
A value written by the application itself rather than entered or read from an outside source by a person.
A system source records that the application produced the value. Nobody typed it and no external document was consulted.
Values derived from other values belong here: a height recomputed when a floor count changes, a region link rebuilt after a pinpoint moves, a flat column refreshed from its data row.
It states provenance, not confidence. A derived value can be perfectly correct, but a reader can see that it rests on other data in the database rather than on an outside source of its own.