NACE classification

NACE is the European Union's classification of economic activities used in official statistics. Its hierarchy lets statistical offices describe production activities at comparable levels across member states. A NACE code classifies an activity, usually at an establishment or statistical-unit level, rather than identifying a legal person. A multi-activity organization may require a principal activity plus additional detail in the underlying source.

Revisions change the boundaries and labels of categories, so a code without its version can mislead historical comparisons. National statistical classifications may add detail while remaining linked to NACE. A code copied from a company directory is not proof of actual current operations. Retain the source unit, version, effective period, and classification evidence when reconciling sector claims.

A fictional policy analyst compares the share of employment in pharmaceutical manufacturing in two member states. Each state publishes data by a national classification derived from NACE, with different levels of detail.

The analyst compares at the class level for the first state and at the group level for the second, because the second state aggregates two classes. The report says so, and shows the comparison at the common group level. The analyst also notes that one state's business register assigns codes at registration while the other reclassifies annually from survey data. The conclusion is limited accordingly: the comparison is valid at the group level for the year given, and differences below that level are not supported by the sources.

NACE is not a company identifier or a product list. It tells you what kind of activity a unit carries out, not who the unit is or what exactly it sells. It is also not identical to NAICS. They share concepts and ancestry, but their boundaries, labels and levels differ, and a mapping must go through published correspondences.

Finally, national extensions look like NACE codes and add digits. A code with five or six characters from a national register may not be comparable with another country's, even if both start with the same four. Record the scheme name and the country with each code.

NACE is revised on a long cycle, and the move between revisions is a substantial event for every dataset that uses it. Eurostat publishes correspondence tables that link old and new classes, and the links are often one-to-many or many-to-many, so a class in one revision can split across several in the next. A time series that crosses a revision needs a stated treatment: recode with weights, restrict to classes that map one to one, or report each period in its own revision. Whichever is chosen, the report should say so and cite the table used. The same applies to national statistical offices that adopt a new revision on their own timetable, which means two countries may be on different revisions in the same year.