Revenue and expenditure data drawn from IoM Treasury Pink Books (Table 3A departmental breakdowns), covering actuals FY2016 through FY2025. Revenue figures represent General Revenue Account (GRA) inflows; departmental gross spend includes GRA allocations and departments' own income. All figures in £000s converted to £m for display.
Last confirmed balance: £596.3m at 31 March 2024 (IoM Treasury Pink Book 2026-27, Table 2). Strategic Reserve Fund market value; this reserve is not designated for a specific purpose. No 31 March 2025 figure published as at 24 June 2026.
Last confirmed AUDITED balance: £1,100.1m at 31 March 2024 (Operating Account + externally-invested Investment Account at market value, DBB 2023-24 Note 12.14.5 — cross-checked against IoMG_Real_Balance_11yr.xlsx). Corrected in v5.7: the series previously shown here (peaking £1,025.1m) was a Pink Book Table 26 book-value rollforward that never marked the Investment Account to market, understating the true fund by a growing margin (£63m in FY15-16 to £131m by FY23-24). The FY2024-25 figure (£1,025.1m, shown dashed/probable) is NOT yet on the corrected basis — audited accounts not yet published — and is likely £100-150m below the true March 2025 market value. The NI Fund is a statutory ring-fenced account; its balance is not part of GRA and does not appear in the revenue account surplus or deficit.
Last confirmed balance: £24.8m at 31 March 2024 (IoM Treasury Pink Book 2026-27, Table 2). The CFR has been in near-continuous drawdown since 2021-22 as capital expenditure has outpaced annual transfer receipts. No 31 March 2025 balance published as at 24 June 2026.
Last confirmed liability: £3,061m (£3.06bn) at 31 March 2024 — IoM Government Annual Financial Statements, year ended 31 March 2024, Note 12.24.3/12.24.4 (FRS102 basis, Central Government). This is the accumulated past-service obligation of the PSPA Unified Scheme, an unfunded defined benefit arrangement. No figure has been published for 31 March 2025 as at 9 July 2026. The liability is absent from every Pink Book headline figure. It is highly sensitive to the real discount rate used: a 0.5% movement changes the liability by approximately ±£350m. The peak of £4,800m in FY2020-21 reflected a low-rate environment; the liability fell to £2,902m at 31 March 2023 as rates rose, then rose again to £3,061m at 31 March 2024 (+£159m) as interest and service costs outweighed the year's actuarial gain — not a one-way improvement.
PSPER: drawn as a true flow node — its height equals gross cash pension payments (AllSchemes fund account / PSPA AR; FY2024-25 = £143.3m confirmed) and its inputs fill it exactly, so node in = node out every year: pensions out = PSPER reserve drawdown + employer superannuation + employee superannuation + GRA net charge. The hatched top segment is the drawdown — pensions paid from the PSPER reserve's own assets (shown as an arrowed flow from the PSPER balance beaker; this reserve is ring-fenced and is NOT the Strategic Reserve Fund). Employer superannuation is the LBB Table 4 actual for every year; employee superannuation is derived as AllSchemes total contributions minus employer superannuation. PSPER balances are confirmed market values (LBB Table 7.6b): £191.6m (Mar 2016) → £9.8m (Mar 2022) → exhausted March 2023, after which the GRA net charge replaces the drawdown. Segment order mirrors source order so no funding ribbon crosses another. Department colour-coding of the outflow uses FY2025-26 employer contribution proportions as a proxy.
Below the line ("from balances"): two flows. (1) The CFR transfer is the Pink Book's own below-the-line appropriation from the revenue account to the Capital Fund (Table 3A). (2) The GRA net pension charge is computed as a residual but reconciles exactly to the PSPA's published Net Treasury Charge plus scheme transfers-in (FY2024-25: 46,220 + 1,093 = 47,313). Both are financed from accumulated Government balances rather than in-year departmental allocations — which sum exactly to GRA inflows, leaving no in-year headroom. v5.5: the hatched section is now MERGED into the GRA node as its foot — the GRA reads as one account whose full height is total throughput: the revenue-funded body on top, the hatched balance-financed segment below, with the inflow = outflow identity still exact.
Where "from balances" actually comes from (v5.3, reconciled): two sources, both now confirmed from the LBB/DBB accounts (Reserves_Reconciliation sheet, master workbook). (1) The GRA's own retained balance — shown as the small "bal" readout beneath the GRA amount (hover for the series). It stood at +£92.0m at March 2020, flipped to deficit in the Covid year (−£7.1m, 2021) and has deepened every year since: −£115.9m (2022), −£165.9m (2023), −£263.9m (2024). (2) Transfers from the Strategic Reserve Fund — £41.9m plus £10.8m of investment income in FY2022-23, £29.2m plus £9.4m in FY2023-24, and £50.0m in FY2024-25. The direction reversed over the decade: in FY2018-19 and FY2019-20 General Revenue paid £20m a year into the Reserve Fund; the £330m bond proceeds passed through General Revenue into the fund in FY2021-22 (~£198m net); since then the fund has been drawn on to support revenue spending.
v5.4 — the Reserve Fund drawn as a source: the Strategic Reserve Fund now appears as a dashed green node between Income Tax and National Insurance, sized to the year's actual transfer (Reserves_Reconciliation sheet). When transfers run INTO General Revenue (FY2017-18 £20.0m; FY2020-21 £7.0m; FY2022-23 £52.8m; FY2023-24 £38.5m; FY2024-25 £50.0m) it feeds the hatched below-the-line extension under the GRA; the remainder of that extension — labelled from GRA balance (overdraft) — is the residual drawn against the GRA's own retained balance. In FY2018-19 and FY2019-20 the ribbon reverses: General Revenue paid £20m a year INTO the fund. FY2021-22 shows the published NET £198m into the fund, which includes £330m of bond proceeds routed through General Revenue — a financing transaction, not revenue. Extension identity: reserve transfer in + overdraft = CFR transfer + pension net charge + transfer out, exact in every year. v5.5: the fund's STOCK is back on the diagram — a dashed green beaker at a fixed position left of the transfer node shows the market value (£559.5m at March 2025) and drains into (or absorbs, in reverse years) the year's transfer via an arrowed flow; hover the beaker for the full series. Beaker positions across the diagram are now fixed between years — only fills, flows and labels move.
v5.4 — departmental pay ribbons: the Employee Costs → pay & benefits ribbons (c4→c6) are subdivided by department and coloured with the departmental palette, using each department's actual share of Employee Costs for that year (LBB Table 4 via the department × category matrix). The allocation of each pay item across departments is proportional — departments' individual PAYE/NI mixes are not published. Focusing a department in the filter lights up only its strips. All c4→c6 ribbons now use the same source→destination colour gradients as the rest of the diagram.
Reserve beakers: Capital Reserve and the FRS102 Pension Liability (last confirmed £3.06bn at 31 March 2024) display alongside PSPER; hover any beaker for its full balance time series. The Reserve Fund balance is shown as a beaker fixed beside its c0 transfer node (hover for the market-value series: v5.3 re-keyed to end-year and FY2023-25 corrected to published actuals — £565.5m, £584.4m, £559.5m; book cost £525.4m at March 2025).
The pay items sum exactly to the Employee Costs node: net wages + PAYE + employee NI + employer NI + pension contributions = Employee Costs. Employer NI is an LBB Table 4 actual for all ten years. Employee NI (est.): employer NI × (12÷13.8) — IoM main rate ratio. PAYE (est.): ~19.5% effective rate on taxable wages. Net wages are the residual. The estimated items are subject to an FoI request to IoMG Treasury Payroll.
Benefit-level splits are now year-specific. FY2018-19 to FY2020-21 use LBB Tables 6.8g/6.8h per-benefit actuals (no tilde), including the FY2020-21 Covid support line (MERA + Salary Support, £78.1m). FY2021-22 onward apply Pink Book base-cost per-benefit proportions to LBB aggregate actual totals and are marked ~ as estimates; FY2015-16 to FY2017-18 carry back FY2018-19 proportions (~). Each year's items sum exactly to the LBB published NI-funded and revenue-funded totals before being scaled to the Pink Book Table 3A node total. The NI/GRA funding split uses the Sankey's own revenue flows.
The underlying FY2016-17 source data contains two confirmed classification breaks that render the raw figures non-comparable with all other years in the series. The figures displayed for FY2017 are accounting estimates, not published actuals.
Break 1 — Revenue misclassification: National Insurance Operating Account receipts (normally ~£187–216m) are absent from the revenue breakdown, and Income Tax is reported at £12m against a plausible range of £184–203m. The excess is absorbed into Other Treasury Income (£261m vs a normal ~£10m). The reconstructed series allocates NI and Income Tax in proportion to the FY16/FY18 ratio, with Other Treasury Income set by interpolation. v5: Customs & Excise and Income Tax are further scaled (+8.1%) so reconstructed revenue fully covers the reconstructed departmental allocations — the published GRA total of £641m left a £40m funding gap against Health & Care's reconstructed allocation, which would have broken flow conservation in the diagram. FY2017 remains an estimate year throughout.
Break 2 — Departmental misclassification: Social Security gross spend collapses to £9m (against a plausible range of £275–318m) while Health & Care doubles to £527m. The excess in H&C matches the Social Security shortfall to within £19m. The reconstruction reclassifies £287m from H&C to Social Security, with GRA flows adjusted proportionally.
The constant prices deflator uses IoM CPI financial-year averages (Statistics IoM Historic Data Sets, December 2025), rebased to 2024-25 = 100. FY2025-26 uses a partial-year average (April–December 2025). Deflation is applied uniformly to all flows; the Sankey layout, stat bar, and time-series popouts all reflect the selected price basis.
FY2016 data is sourced from an earlier Pink Book edition than FY2018 onwards and should be treated with caution in trend analysis. The animation skips directly from FY2016 to FY2018 to avoid misleading transitions through the estimated FY2017 values.
Departmental own income (fees, charges, utilities receipts) bypasses the GRA and flows directly to departments. It is shown as a separate column in the revenue sources panel, connected by ribbons directly to the relevant department group, distinct from GRA allocations.
Employee Costs, Supplies & Services, Agency & Contracted, and Infrastructure represent gross departmental expenditure. Loan & Other includes loan charges, transfers, and net adjustments; negative values in some years reflect internal recoveries or accounting reversals rather than literal income.
Two small inconsistencies exist in the published Pink Book data and are shown as published rather than adjusted: Enterprise own income exceeds its gross spend by £0.7m in FY2021-22 and £0.1m in FY2023-24 (net contributor years), and Treasury Ops records net −£1.0m gross spend in FY2020-21 (its node is suppressed that year). Flow ribbons taper to absorb these differences.