How do you read a one to many split row?

A one to many split row shows one NACE Rev. 2 class split into two or more classes in NACE Rev. 2.1. The Eurostat manual states the definition, and gives the count as 11 NACE Rev. 2 classes. A split row divides an old scope among new classes. A verified split from the manual changelog is used as the worked example in this guide, so that the row form is shown with real codes whose split is stated in the source.

What is the verified split example?

The manual states that class 16.29 in NACE Rev. 2, for manufacture of other products of wood, manufacture of articles of cork, straw and plaiting materials, was split into three new classes in NACE Rev. 2.1: 16.26 for manufacture of solid fuels from vegetable biomass, 16.27 for finishing of wooden products, and 16.28 for manufacture of other products of wood and articles of cork, straw and plaiting materials. Eurostat states the split in the passage on Section C, in the list of major changes for manufacturing. The three new classes together cover the scope that the old class covered, divided by the distinctions stated in their notes. The old heading words appear, in part, in the heading of the third new class, which carries the residual scope, while the first two new classes carry the separated scopes for solid fuels and for finishing.

The example shows why a split row must be read with the notes. The heading of class 16.28 alone does not show that solid fuels and finishing have been removed from its scope, because the heading words for wood, cork, straw and plaiting materials remain. The notes for classes 16.26 and 16.27 state the activities they cover, and the note for class 16.28 states the remainder. A reader who reads only the heading of 16.28 will treat the old scope as unchanged. A reader who reads all three notes will see the division, and will be able to compare the old scope with the new scopes, class by class.

Old class in NACE Rev. 2	New classes in NACE Rev. 2.1, as stated in the manual
16.29 manufacture of other products of wood, articles of cork, straw and plaiting materials	16.26 manufacture of solid fuels from vegetable biomass
Same old class	16.27 finishing of wooden products
Same old class	16.28 manufacture of other products of wood and articles of cork, straw and plaiting materials

How is a split row used for a comparison?

A split row does not support dividing an old total between the new classes without additional information. The old total is a single figure for the old class. The new totals are separate figures for each new class, collected under the new version. The table does not give shares, weights, or conversion coefficients for dividing the old total. Where a backcast series is needed, the correspondence table is the starting point, and the conversion requires underlying data at a finer level, or a parallel tabulation, as described in the guide on comparison over time. A reader who divides an old total by an assumed share, without a source for the share, has added an assumption that the table does not state.

What must be checked in the notes for a split?

Each new class note must be checked for its inclusions, its inclusions also, and its exclusions, with cross references to the other new classes. The manual states that notes highlight boundary issues by providing examples of activities that may appear similar but are classified elsewhere. In a split, the boundary examples are the working detail: an activity that was in the old class may be listed as included in one new class and excluded, with a cross reference, in another new class. The cross references between the new class notes are the map of the split. A reader who reads one new note in isolation will see only part of the map. All new notes in the split, and the old note, must be read together, so that the division of the old scope can be traced in full.

The old note must also be read, because the split may have changed the wording of the scope as well as dividing it. A heading that is reused in a new class, such as the heading for 16.28, may carry a narrower scope than the old heading, even though the words overlap. The note for the new class states the narrower scope, and the notes for the other new classes state what was removed. The comparison of the old note with the new notes is therefore the check that the split has been understood, and the table row is the pointer to the notes that must be compared.

What does a split row not guarantee?

A split row does not guarantee that a particular activity has a new class, and it does not guarantee that the new class can be picked from the row. The row guarantees only that the old scope is divided among the new classes listed, as stated in the manual definition of the one to many type. Which new class covers a particular activity is a question for the notes, and the entry for a unit is a question for the institute or register that holds the record. The row is a warning against a direct comparison with one new class, and a pointer to the notes. It is not a finder, and it must not be used as one.

Trace the split in the manual changelog, read all the new class notes together with the old note, and confirm any entry with the national statistical institute or the business register that holds the record.