What is a statistical unit?

A statistical unit is the entity to which a classification code is assigned in statistics. The United Nations Statistics Division states, for ISIC Rev. 5, that the statistical units are legal entities, enterprises, establishments, and similar units, and the Central Statistics Office states, for NACE, that coding is based on the principal activity of a unit, and that a unit should be classified to the category that best describes its activity. The unit type matters, because the same legal person can contain more than one statistical unit, and the units can hold different codes.

A code quoted without naming the unit type is incomplete, because the reader cannot tell which unit the code belongs to.

What unit types are used?

Three unit types are used most often, and they should be distinguished. A legal entity is a person in law, such as a company, that can own assets, incur liabilities, and enter into contracts. An enterprise is an organisational unit producing goods or services, with autonomy in decision making, and it can contain more than one legal entity, or be part of one. An establishment, also called a local unit, is a part of an enterprise situated in a geographically identified place, at or from which economic activity is carried out. The United Nations Statistics Division lists legal entities, enterprises, and establishments among the statistical units for ISIC, and the same unit types appear in European business statistics, where the enterprise and the local unit are the frames for different outputs. A register entry should state which unit type it describes, and a dataset should state which unit type its figures count. A code for an enterprise is not automatically the code for each of its establishments, and a code for an establishment is not automatically the code for the enterprise that owns it.

How does the unit type affect the code?

The unit type affects the code because the principal activity is assessed for the unit in question, not for the group as a whole. An enterprise that carries on several activities is coded by the activity that contributes most to its value added, in the terms the Central Statistics Office uses for NACE coding, while an establishment inside it is coded by the activity carried on at that place. The two codes can therefore differ, and both can be correct, for their respective units. A kind of activity unit, which aggregates in an enterprise all the parts involved in one activity, is a further unit type used in some statistics, and it is coded by that activity alone. A reader who compares a code for an enterprise with a code for an establishment, without naming the unit types, compares two different assessments, and the difference should be recorded as a unit difference, not as a coding error. The correspondence table and the explanatory note do not resolve a unit difference. The unit definition in the metadata does.

How is the unit named in a check record?

The unit is named in a check record by its type and its identifier, together. The identifier is the register identifier for the unit, such as the SIREN number for a legal unit in France, as Service Public states for the Sirene tool, or the business identifier in the KVK record in the Netherlands, as Statistics Netherlands describes. The type is the unit type as shown in the record: legal entity, enterprise, establishment, or local unit. A check record that gives the identifier without the type leaves the reader to guess which unit was checked, and a record that gives the type without the identifier leaves the reader unable to repeat the check. The table below shows the record shape, with the unit row given the same weight as the code row, so that a reader does not treat the unit as a detail and the code as the substance, when the code only has substance for a named unit.

Record item	What to state
Unit type	Legal entity, enterprise, establishment, or other unit, as shown
Unit identifier	Register identifier for that unit, as shown
Code	Code as held for that unit, copied exactly
Classification version	NACE Rev. 2, NACE Rev. 2.1, or the national version
Check date	Date the record was consulted

The table is the minimum for a unit check. A record that omits the unit type should be completed before the code is quoted, by opening the register entry or the dataset metadata and recording the type stated there.

What does a statistical unit not decide?

A statistical unit does not decide the legal, tax, or licensing position of the person behind it. The unit is a statistical construct, defined for the collection and presentation of statistics, and its boundaries can differ from legal boundaries, from tax boundaries, and from licensing boundaries. A legal entity can contain several statistical units, and a statistical unit can span more than one legal entity, in the case of an enterprise group. The EUR-Lex summary states that the NACE legislation only applies to the use of the classification for statistical purposes, and the unit definitions share that limit. A question about the legal position of a person belongs to the law that governs that position, and the statistical unit should never be quoted as if it decided it.

Where is a unit confirmed?

A unit is confirmed in the register that holds the record for that unit, with the unit type and identifier stated, and in the dataset metadata, for the unit type counted in a statistic. The meaning of the category assigned to the unit is confirmed in the Eurostat explanatory notes, and the move between versions in the correspondence tables. Confirm the unit type and identifier first, then the code, and confirm a business entry with the institute or register that holds the record for that unit.