How do you use a note before a correspondence table?

A note is used before a correspondence table by reading the note for the category in the version concerned, to establish what the category covers, and then reading the table row for that category, to establish how the category relates to categories in the other version. The note first sequence ensures that the scope is known before the relationship is read, so that a table row is not misread as a definition. A table row states a relationship between scopes. Without the notes, the scopes are unknown, and the relationship cannot be understood.

What is the checking sequence, step by step?

The sequence is illustrated by the verified wood split. The note for the old class 16.29 states the old scope. The notes for the new classes 16.26, 16.27 and 16.28 state the divided scopes. The table row for 16.29 states the one to many type and lists the new classes. A reader who starts with the table will know that a split happened, and will know the new classes, but will not know which part of the old scope each new class covers. A reader who starts with the notes will know the scopes, and will then see, in the table, that the scopes together form the old scope, divided as the notes state. The note first sequence therefore gives the meaning, and the table then gives the relationship that confirms the meaning across versions.

Step	Source and what it provides
1. Identify	Category code, heading, and version stated
2. Read the note	Description, includes, includes also, excludes, cross references, in that version
3. Read the parents	Group, division and section notes, for the frame and the boundary
4. Read the table	Row or group, direction, table version, and type
5. Read the other side	Notes for the categories in the other version, for the divided, combined or preserved scope

Why must the note come before the table?

The note must come before the table because the table is a relationship between scopes, and a relationship cannot be read without knowing the scopes. A one to many row, read without the notes, looks like a list of new codes, and a reader may pick one code from the list as if it were the new code for an activity. A many to many group, read without the notes, looks like a set of pairings, and a reader may pair one old code with one new code as if the table stated that pairing. Both errors are avoided by reading the notes first, because the notes state which part of the old scope each new class covers, and they state that the group scope is identical only as a joint scope. The table then confirms the relationship that the notes already show, and the type names the relationship in the terms used by Eurostat.

The note first sequence also protects against a version error. A table row quoted without a version label cannot be verified, and a note quoted without a version label cannot be verified either. Reading the note first, with its edition stated, establishes the version for the scope. Reading the table second, with its version stated, establishes whether the table consulted matches the note edition, or whether a later table version has revised the row. A mismatch must be noted and resolved, by checking the current table and the current note on ShowVoc, rather than by treating the first source found as current. The sequence makes the version check explicit at each step, instead of leaving it to the end.

What is checked after the table?

After the table, the notes on the other side are checked, and then the institute or register is consulted for an entry. The notes on the other side confirm the scope in the other version, and they show whether a heading that looks the same in both versions carries the same scope, or a different scope after a split, merger, or restructuring. The correspondence type, read with both sets of notes, states the relationship completely: identical scope, divided scope, combined scope, or joint scope identity for a group. A comparison of statistics can then be made at the level the type supports: direct comparison for one to one, added comparison for many to one, group comparison for many to many, and no direct individual comparison for one to many without additional data.

An entry is checked last, with the institute or register that holds the record, because the entry is an assignment for a unit, not a category relationship. The institute or register applies the classification rules, including the value added and top down rules, to the information held about the unit, and it holds the entry that results. A reader who has completed the note and table sequence has the category information needed to put a question to the institute or register, with the facts about the activity as recorded there. That reader has not determined the entry, and must not present the category found as the entry, before the institute or register has confirmed it.

What does the sequence not guarantee?

The sequence does not guarantee that a move can be converted into a series, or that an entry will be a particular code. It guarantees that the move has been understood as a category relationship, with the scopes stated in the notes and the type stated in the table. Conversion of a series requires, in addition, underlying data at the level needed for the type, or a published backcast or double reported series. An entry requires, in addition, the information held about the unit and the application of the rules by the institute or register. The sequence is a reading method for categories. It is not a conversion method, and it is not an assignment method, and it must not be presented as either.

Read the note first, read the table row with its type and version, and confirm any entry with the national statistical institute or the business register that holds the record.