Supplier Tax registration number and Taxpayer ID, which field to use?

Hi. I can't find any documentation which explains the purpose/use of Tax registration/Taxpayer IDs in the Supplier records.

Suppliers have different registration numbers and we are not sure which fields to use.

Currently, we are unsure where to map these numbers:

France - SIREN, SRT, Social Security Number and SSR

New Zealand- TAX DISTRICT Reference Number

TAX REGISTRATION NUMBER FIELD IN SUPPLIER PROFILE AND ADDRESS

CREATE TAX REGISTRATION NUMBER

TAXPAYER ID IN INCOME TAX TAB

FOR YOUR KIND ASSISTANCE PLEASE. THANKS