Add the 2015–2017 Housing Benefit non-dependant deduction scale history #2212

Summary

Approved plan A5 adds the enacted 2015–2017 income thresholds and deduction amounts to the one existing Housing Benefit scale document. It currently backdates 2018 values. Three files, no inputs or formula changes. Existing #1925 retains 2018 onward scale changes and #2007/#2017 retain banding, exemptions and non-dependant attribution. 2015 non-dependant deduction scale (Article 18(3): all six amounts and income thresholds); 2016 non-dependant deduction scale (Regulation 5: all six amounts and income thresholds); 2017 non-dependant deduction scale (Article 23(3): all six amounts and income thresholds)

Audited model surface

• Audited release: policyengine-uk 2.106.1
• Audit unit: variable:household_benefits_individual_non_dep_deduction
• Last model modification: 2024-07-25
• Explicitly reviewed units:
  • variable:household_benefits_individual_non_dep_deduction — last model modification: 2024-07-25
• Audit date: 2026-10-09
• Periods reviewed: 2015–2017 complete scale; retain existing 2018 onward values
• Jurisdictions: Great Britain

Findings and implementation parts

1. The existing scale lacks the 2015–2017 thresholds and amounts.

Sources: 2015 non-dependant deduction scale (Article 18(3): all six amounts and income thresholds); 2016 non-dependant deduction scale (Regulation 5: all six amounts and income thresholds); 2017 non-dependant deduction scale (Article 23(3): all six amounts and income thresholds)

• Add all six threshold and amount histories for 2015, 2016 and 2017 with dated official citations, precise raw-scale regression tests and a changelog. Do not duplicate later-rate or exemption PRs. 2015 non-dependant deduction scale (Article 18(3): all six amounts and income thresholds); 2016 non-dependant deduction scale (Regulation 5: all six amounts and income thresholds); 2017 non-dependant deduction scale (Article 23(3): all six amounts and income thresholds)
  • Add or update reference at policyengine_uk/parameters/gov/dwp/housing_benefit/non_dep_deduction/amount.yaml → brackets[*].threshold/amount dated references using 2015 non-dependant deduction scale (Article 18(3): all six amounts and income thresholds); 2016 non-dependant deduction scale (Regulation 5: all six amounts and income thresholds); 2017 non-dependant deduction scale (Article 23(3): all six amounts and income thresholds).

Uncertainties and exclusions

Historical table only. No change to gross income, equality/banding consumers or exemption rules; #2007 owns those, before #2017. Rebase after #1925 to keep later years. Tests inspect the table independently of those unchanged consumers.