Five-Year Classification Review Cycle

NAICS undergoes mandatory review every five years for potential revision. This isn’t optional maintenance, it’s built into the system’s governance.

The cycle works:

  1. Office of Management and Budget publishes Federal Register notice soliciting public comments
  2. Economic Classification Policy Committee evaluates proposals for new/modified industries
  3. Changes are evaluated against existing principles (production-oriented, single-framework)
  4. Approved changes take effect in the next census year
  5. Historical data is restated where practicable

The pattern generalizes: any classification or ontology governing shared data needs a defined review cadence, public input mechanism, explicit evaluation criteria, and a process for propagating changes to historical records.

Without governance structure, classifications either freeze (becoming irrelevant) or drift (becoming inconsistent). The five-year cycle is a Goldilocks compromise, frequent enough to track economic change, infrequent enough to maintain analytical stability.

For knowledge engineering: ontologies need the same discipline. Version control, deprecation policies, and stakeholder review processes aren’t overhead, they’re what makes a controlled vocabulary controlled.

Related: 02-atom—time-series-continuity-tension