Exempt unit trusts and stocks and shares ISAs from the sale-expense deduction

.github/CONTRIBUTING.md

@@ -46,6 +46,14 @@ and add `verified_end_year` when verified coverage has a defined end. Change the
 verified year fields only after confirming that parameters and tests cover the
 stated years.
 
+## Axiom parity
+
+Every policy change here must also be correct in [rulespec-uk](https://github.com/TheAxiomFoundation/rulespec-uk). That covers a new programme, a parameter or threshold update, an eligibility rule and a bug fix. The shared guide, [Mirror policy changes in Axiom](https://github.com/PolicyEngine/.github/blob/main/CONTRIBUTING.md#mirror-policy-changes-in-axiom), defines the `axiom:` line your PR description needs and what a `queued` issue must contain. UK specifics:
+
+- National modules live under `uk/`, and council schemes such as council tax reduction live under `uk-<council>/`. Search `main` there before opening a new issue.
+- An `encoded-correct` claim names the module and a companion case in its `.test.yaml` that exercises the same situation as your YAML test.
+- Use `queued` only when the signed encoder is blocked; record the blocker in the issue. Each billed encoder run requires separate approval. Label `queued` issues `pe-parity`. Reuse your YAML test's externally sourced expected values (legislation.gov.uk, gov.uk guidance, official calculators) as the companion tests; don't copy values computed by policyengine-uk.
+
 ## Repo-specific anti-patterns
 
 - **Don't change HF upload destinations** in the `policyengine-uk-data` upload pipeline without explicit authorisation — the private/public split exists to respect the UK Data Service licence.

.github/PULL_REQUEST_TEMPLATE.md

@@ -0,0 +1,12 @@
+Fixes #
+
+## What and why
+
+## Test plan
+
+- [ ] For policy changes: YAML tests whose expected values come from an external source (legislation, official guidance, official calculator); otherwise mark not applicable.
+- [ ] `make format`
+- [ ] Changelog fragment in `changelog.d/`
+
+<!-- Required for any change to policy (programmes, parameters, eligibility, bug fixes). See .github/CONTRIBUTING.md ("Axiom parity"). Keep one standard option below, or use axiom: needed if you are an external contributor who cannot complete the Axiom work; a maintainer will follow up. -->
+axiom: <legal id> encoded-correct | <rulespec-uk PR> encoded | <rulespec-uk issue> queued | n/a: <reason>

CHANGELOG.md

@@ -1,3 +1,64 @@
+## [2.113.6] - 2026-10-04
+
+### Changed
+
+- Document what `pension_credit_reported_capital` must contain (countable capital after the Schedule V disregards and reg. 19 valuation) and what it replaces, and restate its monotonicity property around the savings credit's intended exception.
+
+
+## [2.113.5] - 2026-10-04
+
+### Fixed
+
+- - Corrected pension-age Housing Benefit and Council Tax Reduction premiums by removing adult disability and adult enhanced disability premiums absent from their statutory schedules and applying the severe disability premium's qualifying-benefit, couple, Housing Benefit non-dependant and shared carer-attribution conditions. The carer condition does not yet count Universal Credit carer-element awards (#2120).
+
+
+## [2.113.4] - 2026-10-04
+
+### Changed
+
+- - Documented that policy changes must be mirrored in Axiom RuleSpec (rulespec-uk), and added a pull request template with the required `axiom:` line.
+
+
+## [2.113.3] - 2026-10-04
+
+### Fixed
+
+- Split additional State Pension by each person's State Pension type in the year simulated, as basic and new State Pension already are, instead of their type in the data year. Survey ages are held fixed across projected years, so records that were on the basic State Pension in the data year stand for new State Pension cohorts later, and the part of their reported State Pension between the two flat rates was paid twice. Basic, new and additional State Pension now add up to the reported amount uprated by the flat rate.
+- Council Tax Reduction income now counts Carer Support Payment, which Scottish carers receive in place of Carer's Allowance (Council Tax Reduction (Scotland) Regulations 2021 reg 57(1)(b)(iva); Council Tax Reduction (State Pension Credit) (Scotland) Regulations 2012 reg 27(1)(j)). The Scottish Carer Supplement stays out.
+
+
+## [2.113.2] - 2026-10-04
+
+### Fixed
+
+- Deduct from each person's Universal Credit earnings only their own income tax and National Insurance on that employment or self-employment (UC Regs 2013 reg. 55(5)(b), reg. 57(2) step 3), not the whole benefit unit's tax on all income, so tax on pensions, State Pension, property, savings and dividends, the High Income Child Benefit Charge and voluntary Class 3 contributions no longer reduce earned income.
+
+
+## [2.113.1] - 2026-10-04
+
+### Changed
+
+- - Documented that `afcs_reported` is FRS benefit code 8 (Armed Forces Compensation Scheme payments and war disablement pensions, not armed forces independence payment) and tested that AFCS payments never confer severe disability.
+
+
+## [2.113.0] - 2026-10-04
+
+### Added
+
+- - Give joint tenants and other sharers their share of the household's rent, boarders and lodgers their own rent and private tenure, a Housing Benefit LHA category (with its own size criteria and shared-accommodation rule) beside the Universal Credit one, statutory non-dependant exclusions and apportionment, the Housing Benefit meals deduction, and Council Tax Reduction on the council tax divided among jointly liable people, each claim under its own family's scheme and exemption from non-dependant deductions.
+
+
+## [2.112.1] - 2026-10-03
+
+### Fixed
+
+- The legacy severe disability premium and the Pension Credit severe disability addition now share one attribution of whom each carer benefit is paid for caring for (`is_cared_for_by_carer_benefit_recipient`), so a carer in another benefit unit of the household bars the legacy premium as it already barred the addition, even when that carer is ignored as a non-dependant.
+- - Counted a trading loss for Class 4 NICs only in the year it is entered for, so a one-off `trading_loss` is relieved once and only its unrelieved part reduces later years' profits (new `ni_class_4_trading_loss`).
+  - Isolated supplied-input provenance between simulation clones and removed it for deleted inputs, preventing Class 4 from relieving cached carry-over losses again.
+  - Corrected the Class 4 property-test reference to use each year's trading allowance parameter, including the zero allowance in historical years.
+- - Charged Class 4 NICs on the profits chargeable under ITTOIA 2005 Part 2 Chapter 2, after capital allowances and the trading allowance, less trading losses under SSCBA 1992 Sch. 2 para. 3 (new `ni_class_4_profits`). Losses reduce only trade profits for Class 4 and carry forward until used.
+
+
 ## [2.112.0] - 2026-10-03
 
 ### Added

changelog.d/add-isa-balance-variables.added.md

@@ -0,0 +1 @@
+- Add `cash_isa` and `stocks_and_shares_isa` Household wealth input variables for ISA balances.

changelog.d/sale-expense-share-split.fixed.md

@@ -0,0 +1 @@
+- Apply the 10% sale-expense deduction to directly held shares only, so unit and investment trusts (ADM H1673-H1674) and stocks and shares ISAs (ADM H1656) count at full value in every means test; datasets that do not itemise `corporate_wealth` keep its previous treatment.

changelog.d/wealth-share-components.added.md

@@ -0,0 +1 @@
+- Add `directly_held_shares` and `unit_and_investment_trusts` household inputs for the share-like components of `corporate_wealth`, count them and the stocks and shares ISA in place of `corporate_wealth` in every means-test capital sources list (with `unitemised_corporate_wealth` carrying any part a dataset does not itemise), and uprate them and the ISA balances with per-capita GDP.

docs/book/assumptions/growthfactors.md

@@ -60,7 +60,7 @@ We derive these rates from OBR GDP growth and ONS population projections.
 |-------------|------|------|------|------|------|------|------|------|
 | Growth rate | 9.2% | 5.0% | 3.8% | 2.8% | 2.8% | 3.1% | 3.3% | 3.3% |
 
-We use per capita GDP for these variables: `capital_gains`, `capital_gains_badr`, `capital_gains_before_response`, `capital_gains_carried_interest`, `capital_gains_residential_property`, `corporate_wealth`, `dividend_income`, `gross_financial_wealth`, `household_lifetime_isa_balance`, `lifetime_isa_balance`, `lump_sum_income`, `main_residence_value`, `maintenance_income`, `miscellaneous_income`, `mortgage_capital_repayment`, `net_financial_wealth`, `non_residential_property_value`, `other_investment_income`, `other_residential_property_value`, `owned_land`, `pension_income`, `private_pension_wealth`, `private_transfer_income`, `property_income`, `savings`, `savings_interest_income`, `sublet_income`
+We use per capita GDP for these variables: `capital_gains`, `capital_gains_badr`, `capital_gains_before_response`, `capital_gains_carried_interest`, `capital_gains_residential_property`, `cash_isa`, `corporate_wealth`, `directly_held_shares`, `dividend_income`, `gross_financial_wealth`, `household_lifetime_isa_balance`, `lifetime_isa_balance`, `lump_sum_income`, `main_residence_value`, `maintenance_income`, `miscellaneous_income`, `mortgage_capital_repayment`, `net_financial_wealth`, `non_residential_property_value`, `other_investment_income`, `other_residential_property_value`, `owned_land`, `pension_credit_reported_capital`, `pension_income`, `private_pension_wealth`, `private_transfer_income`, `property_income`, `savings`, `savings_interest_income`, `stocks_and_shares_isa`, `sublet_income`, `unit_and_investment_trusts`
 
 ## Council tax