How the Arrow Index is built

One entry is one meaningful change to an immigration law or rule: who may enter a country, stay, work, study, or become a citizen. We date it to the day it took effect and assign it to a single country.

A single legal instrument counts once, however many provisions it amends. Routine form updates, filing instructions, and processing notices are left out, so the count tracks substance rather than paperwork.

This release does not publish tightening or easing labels because the rebuilt bundle did not assign them under its frozen counting rules.

We read each country's official gazettes and government publications. An entry joins the index only when a public document supports what we say changed, and that document is linked from the entry.

The record is Arrow's own research. Ongoing monitoring adds new changes as governments publish them. The historical record is built by working through official sources year by year, back to 2010.

Models independently checked the accepted records against preserved source passages. That is machine review, not human verification.

The count for a country is a floor, not a total. If a change is missing, that means we have not verified it yet, not that nothing happened.

Be careful when comparing countries. Governments publish in different ways, so a higher count can mean more change or simply more detailed publishing. We do not certify country-to-country comparisons.

This site renders one frozen, versioned release bundle, so a figure cited against its release number stays true. The 2026 series is partial through 25 August 2026.

The current citable release is five-country-2010-20260825-v2-automated-final. Every release is listed in the changelog, with what changed between releases.

Every country page carries its coverage label, always in the same place. The label states how far back the settled record for that country runs. “Monitoring” means we track new changes as they are published while the historical record is still being researched.

• AustraliaFrom 2010
• CanadaFrom 2010
• New ZealandFrom 2010
• United KingdomFrom 2010
• United StatesFrom 2010

The index is published under CC BY 4.0. Quote it or reprint the figures with the source and exact release number. The complete review bundle is prepared for independent human review.

Arrow Intelligence. (2026). Arrow Immigration Policy Volatility Index (Release five-country-2010-20260825-v2-automated-final) [Data set]. https://witharrow.ai/volatility-index

Every entry carries a “flag this entry” link. Practitioners: if you have filed under a change we haven't recorded, submit it. Accepted corrections ship in the next monthly release and appear in the changelog. The full policy is on the Corrections & Revisions page.