Converting nomenclatures: Principles

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For a given country/period, the nomenclature/version used to organize data is called the native nomenclature. There may be cases where you want to use an alternative nomenclature to produce results in a more practical way. Alternative nomenclatures are called derived nomenclatures. Data to be exposed using a derived nomenclature must go through a process to convert from the native nomenclature/version to the derived nomenclature/version.

WITS offers a lot of flexibility for converting data into other (derived) nomenclatures. Data can be converted from a more detailed nomenclature/version to a less detailed one.

Example of conversion

Nomenclature A	Nomenclature B
Product 1 Product 2 Product 3	Product a
Product 4	Product b

As presented in the above table, products 1, 2 and 3 from nomenclature A are allocated to product a in nomenclature B while product 4 from nomenclature A is allocated to product b in nomenclature B.

Available Concordances:

Derived Nomenclatures

Native
Nomen.

H
S
1

H
S
0

S
I
T
C
3

S
I
C
T
2

S
I
T
C
1

G
T
A
P

M
T
N

B
E
C

C
C
C
N

C
P
C

I
S
I
C
3

I
S
I
C
2

U
S
S
I
C

HS2

HS1

HS0

SITC3*

SITC2*

SITC1*

* SITC nomenclatures are native in UN COMTRADE database only.

As you can see from the above table, most concordances derive from the HS nomenclature since it's the most detailed. For more information on each and every nomenclature, see Understanding Nomenclatures.

As you will see later in this course, concordances are not available in every WITS module. For example the Quick Query modules return data in their native nomenclature only while the Advanced Query module can produce result tables using any derived nomenclature.

In UN COMTRADE, UNSD automatically converts data in any HS and SITC versions, starting from the nomenclature/version used by the country to report information. Therefore, data may be available natively in several nomenclatures/versions in UN COMTRADE. If country reports in HS2, data will be also natively available from UN COMTRADE in HS1, HS0, SITC3, SITC2 and SITC1. If another country reports in HS0, data will be also natively available in SITC3, SITC2 and SITC1 only. You will be able to compare data for these two countries only by using one of the shared native or derived nomenclatures/versions.

The next topic demonstrates how to check available product concordances in WITS.

Next: Checking product concordances

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