Historical relationships · pilot-2026-09-13

Historical crosswalks

Join keys across a documented boundary or currency change without silently treating past and present as identical.

Limited reference pilot

Skagafjörður municipality merger only; Croatia currency changeover only. Other countries/localities and dates are explicitly out of coverage. Covered dates: 1 January 2022 to 13 September 2026. Earlier origins and future changes are not asserted.

Municipality boundary lookup

Skagafjörður and Akrahreppur merged on 29 May 2022. Try a code before and after that date.

Municipality codeSource dateTarget date

matched

5716 · Skagafjörður

A boundary change occurred. Review measure semantics before aggregating; reverse mappings require external allocation weights.

Relationship: merge. Allocation weights: not supplied.

Open this JSON lookup

Covered municipality keys

Download relationship CSV Download provenance

Code	Name	Valid from	Valid until, exclusive
5200	Sveitarfélagið Skagafjörður	Earlier origin outside pilot	2022-05-29
5706	Akrahreppur	Earlier origin outside pilot	2022-05-29
5716	Skagafjörður	2022-05-29	Open within pilot coverage

A two-to-one merger can support aggregation only after reviewing whether a measure is additive and whether every predecessor is included. A reverse join produces two targets and requires allocation evidence. Datahub never assigns weights or copies a total to each target.

Country and currency over time

Croatia changed its currency of account to EUR on 1 January 2023. Cash circulation had a separate transition period.

Country code or nameAs-of dateRelationship

matched

EUR

Country-currency membership only; no conversion or exchange rates.

Open this JSON lookup

Covered country-currency relationships

Download relationship CSV Download provenance

Country	Currency	Role	Valid from	Valid until, exclusive
HR / HRV / 191	HRK	account	Earlier origin outside pilot	2023-01-01
HR / HRV / 191	EUR	account	2023-01-01	Open within pilot coverage
HR / HRV / 191	HRK	cash	Earlier origin outside pilot	2023-01-15
HR / HRV / 191	EUR	cash	2023-01-01	Open within pilot coverage

Reuse and attribution

Keep the provenance download with your CSV. It records the reference version, filters, attribution and reuse terms.

Factual identifier pilot; dataset reuse terms unresolved · unresolved

Sources: Icelandic ministry merger announcement and Skagafjörður municipality notices. Retain the original source URL on each relationship and entity, effective dates and pilot coverage.

This bounded pilot identifies relationships only; it supplies no geometry, allocation weights or licence for a complete historical municipality database.

Reviewed 2026-09-13 · Next review 2026-12-13 · Datahub maintainer

Factual changeover pilot; dataset reuse terms unresolved · unresolved

Source: European Central Bank, Croatia euro changeover. Retain the original source URL, effective dates, account/cash role and pilot coverage.

This bounded pilot supplies membership facts, not exchange rates or a worldwide historical currency database. Source availability is not a blanket redistribution licence.

Reviewed 2026-09-13 · Next review 2026-12-13 · Datahub maintainer

UN M49 reference; exact redistribution basis unresolved · unresolved

United Nations Statistics Division, M49; reference snapshot date. Localized names derive from Unicode CLDR.

UN general website terms are not a verified open-data licence for the M49 snapshot. Confirm dataset-specific permission before claiming unrestricted or commercial redistribution. This is a terms-review gap, not a finding of infringement.

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Reviewed 2026-09-13 · Next review 2026-12-13 · Datahub maintainer

Unicode License V3 · reviewed

Retain the Unicode copyright and permission notice with redistributed data or accompanying documentation. No endorsement by Unicode is implied.

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Reviewed 2026-09-13 · Next review 2026-12-13 · Datahub maintainer

Source governance and corrections

Connect and interpret

GET /api/dimensions/crosswalks
GET /api/dimensions/crosswalks?kind=municipality&code=5200&sourceDate=2022-05-28&targetDate=2022-05-29
GET /api/dimensions/crosswalks?kind=country-currency&country=HR&date=2023-01-01&role=account

Dates are inclusive from and exclusive to. Null means the original boundary is outside the verified pilot, not proof of unlimited historical coverage. Relationships identify keys only. No statistical aggregation, value copying, area/population weights or exchange rates are supplied.

Country lookup accepts ISO2, ISO3, numeric code or a country name through the shared Country dimension. Missing pilot coverage returns an explicit out-of-coverage result. The current Currency dimension need not contain retired HRK; historical membership retains its original code.

Sources and scope

This pilot contains factual identifier relationships with source attribution. It does not include licensed map geometry, postcodes, a complete Icelandic municipal history or a worldwide historical currency database. Expanding those collections requires reviewed authoritative coverage and a validated analysis use case.