# Outlook datasets: what's coming, the tax gap, and welfare in both directions

Six datasets about the public finances looking forward, and about money that
is not collected or not paid correctly. Built nightly by
`pipeline/src/outlook/`; run them on their own with
`npx tsx sites/wymg/pipeline/src/outlook/run-cli.ts [--only=obr,fraud,uc,changes,taxgap]`.

Every file has the same envelope (`Envelope<T>` in `pipeline/src/outlook/common.ts`):

| Field | What it holds |
| --- | --- |
| `id` | The file name without `.json`. |
| `title` | What the dataset is. |
| `generatedAt` | When the pipeline wrote it (ISO timestamp). |
| `geography` | The ONS code and name of the area the figures cover (`K02000001` United Kingdom, `K03000001` Great Britain), with a note where parts of it cover less. |
| `units` | The money unit, where one applies to the whole file. |
| `sources` | Every source read: id, name, publisher, landing page, exact file, publication date, edition, licence id (from `config/licences.json`), and how it was obtained where that matters (for example a Freedom of Information request). |
| `data` | The dataset itself (schemas below). |
| `notes` | What a reader of the file needs to know, in plain words. |

Nothing in these files is worked out on the page: shares, ranges across
forecast editions, changes over time, worked household examples and the
summary tables are all calculated in the pipeline. Years are financial years
(`"2025-26"`) unless a field says otherwise. Money is cash terms (not adjusted
for inflation).

## Files

| File | What it holds | Schema (TypeScript) | Geography |
| --- | --- | --- | --- |
| `changes.json` | Announced tax, benefit and levy changes with start dates, who they affect, official costings (£ million a year, + means the Exchequer gains), distributional analysis where published, and worked examples for typical households; the full scorecard of the two most recent fiscal events; the fiscal event calendar. | `ChangesData` in `changes.ts` | UK (some changes apply only in England or Great Britain; each says so) |
| `welfare-forecast.json` | The OBR's welfare spending forecast from every edition since October 2024 (so vintages can be compared), by benefit and by group, as a share of GDP, health and disability spending, the range across editions, the fiscal rules and welfare cap at the latest assessment, the UC fraud and error forecast, and the long-term state pension projections under three uprating rules. | `WelfareForecastData` in `obr.ts` | UK |
| `long-term.json` | The OBR's long-term projections: spending, receipts and debt as a share of GDP to 2075-76, debt under each scenario, fuel duty, health variants, and what drives the rise in borrowing. | `LongTermData` in `obr.ts` | UK |
| `uc-immigration.json` | People on Universal Credit by immigration status, monthly from April 2022; employment by status and nationality; and, kept separate, DWP's Freedom of Information figures on UC paid to households with at least one non-British, non-Irish national, with DWP's definitions. | `UcImmigrationData` in `ucImmigration.ts` | Great Britain |
| `fraud-error.json` | Benefit overpayments by benefit and year (fraud, claimant error, official error, with confidence intervals), underpayments, unfulfilled eligibility, take-up and unclaimed amounts, tribunal appeals and outcomes by benefit, waiting times, PIP mandatory reconsiderations, HMRC tax credits error and fraud, and a summary row per main benefit putting fraud, official error, underpayment and appeals side by side. | `FraudErrorData` in `fraudError.ts` | Great Britain (PIP statistics: England and Wales) |
| `tax-gap.json` | HMRC's tax gap in £ and as a share of liabilities from 2005-06, by tax, customer group and behaviour, avoidance by tax, which parts are growing, revisions, counts of named avoidance schemes and GAAR opinions, and a comparison with benefit fraud and error on the same axis. | `TaxGapData` in `taxGap.ts` | UK |

Files starting `.last-good-` are the pipeline's fallback copies of each
source's last successful read and are not part of the dataset.

## Keys

- Geography: ONS codes, as above. None of these sources is published below
  Great Britain level except where a file says so.
- Benefits: kebab-case ids from the publisher's own names
  (`universal-credit`, `personal-independence-payment`, `all-benefits`).
- Immigration status: `cta` (British, Irish or right of abode), `euss`, `ilr`,
  `refugee`, `limited-leave`, `humanitarian`, `other`, `unrecorded`.
- Months: `"2026-05"`. Forecast editions: `"march-2026"`.

## Forecasts and vintages

Every forecast figure carries the edition it comes from. `welfare-forecast.json`
keeps each OBR edition since October 2024 under `vintages`; the newest is
`latest`. The range across editions (`totalRange`) shows how far the forecast
has moved between editions; it is not a statistical confidence interval.
When a newer edition is published, the next nightly run adds it and the page
labels the older ones as superseded.

## Sources and licences

| Source id | Publisher | What | Licence |
| --- | --- | --- | --- |
| `obr-efo-*` | Office for Budget Responsibility | Economic and fiscal outlook: detailed forecast tables (expenditure) and chapter 4 and 7 charts and tables | Open Government Licence v3.0 |
| `obr-wtr` | Office for Budget Responsibility | Welfare trends report: charts and tables | Open Government Licence v3.0 |
| `obr-frs-*` | Office for Budget Responsibility | Fiscal risks and sustainability: charts and tables | Open Government Licence v3.0 |
| `obr-policy-measures` | Office for Budget Responsibility | Policy measures database | Open Government Licence v3.0 |
| `hmt-budget-2025` | HM Treasury | Budget 2025 Table 4.1, Table 4.2 and policy costings | Open Government Licence v3.0 |
| `hmt-impact-on-households-2025` | HM Treasury | Impact on households (quoted, not reproduced) | Open Government Licence v3.0 |
| `dwp-fraud-error` | Department for Work and Pensions | Fraud and error in the benefit system | Open Government Licence v3.0 |
| `dwp-unfulfilled-eligibility` | Department for Work and Pensions | Unfulfilled eligibility in the benefit system | Open Government Licence v3.0 |
| `dwp-take-up` | Department for Work and Pensions | Income-related benefits: estimates of take-up | Open Government Licence v3.0 |
| `dwp-pip-statistics` | Department for Work and Pensions | Personal Independence Payment statistics, table 5B(i) | Open Government Licence v3.0 |
| `dwp-uc-immigration` | Department for Work and Pensions | Universal Credit statistics: immigration status and nationality tables | Open Government Licence v3.0 |
| `dwp-annual-report-2025-26` | Department for Work and Pensions | Annual report and accounts (prosecutions, penalties, correction exercises) | Open Government Licence v3.0 |
| `moj-tribunals` | Ministry of Justice | Tribunals statistics quarterly: Social Security and Child Support tables | Open Government Licence v3.0 |
| `hmrc-tax-gap` | HM Revenue and Customs | Measuring tax gaps tables | Open Government Licence v3.0 |
| `hmrc-annual-report-2025-26` | HM Revenue and Customs | Annual report and accounts (compliance yield, cost of collection, prosecutions, repayments, Child Benefit and tax credits error and fraud) | Open Government Licence v3.0 |
| `hmrc-tax-credits-error-fraud` | HM Revenue and Customs | Child and Working Tax Credits error and fraud statistics, Annex B | Open Government Licence v3.0 |
| `hmrc-named-schemes`, `hmrc-gaar-opinions` | HM Revenue and Customs | Counts only: entries by date of publication and legislation, opinions by date | Open Government Licence v3.0 |
| `dwp-foi-2026-83815` | Department for Work and Pensions (via the Centre for Migration Control) | FOI response on UC paid to households with a non-CTA national, 2025. Not official statistics. | Quoted with attribution (`cited`) |
| `rf-stairway-to-headroom` | Resolution Foundation | Distributional analysis of Budget 2025 (quoted) | Quoted with attribution (`cited`) |

Views attributed to named people and organisations (the `panels` in each
file's hand-kept section) are short quotations or summaries, each with its
date and link, under the `cited` licence: they are not ours to relicense.
Quotations marked `verified: false` in `config/outlook.json` could not be
checked against their source and are never shown on the site.

## How the nations differ, and what is done about it

- DWP statistics cover Great Britain; Northern Ireland runs its own social
  security system. The OBR's welfare forecast covers the UK.
- Personal Independence Payment statistics cover England and Wales: Scotland
  replaced PIP with Adult Disability Payment from 2022, whose appeals go to
  the Scottish tribunal and are not in the Ministry of Justice figures.
- Some announced changes apply only in England (the High Value Council Tax
  Surcharge, business rates) or Great Britain (VAT on domestic electricity).
  Each change says where it applies; no figure is adjusted for this.