2c51954790
All checks were successful
ci/woodpecker/push/woodpecker Pipeline was successful
NW seed at £1.5M was nearly clipping in the BigNumber inputs. Widened the form column 420→480px, switched the anchor row to a weighted 1.4/1.2/0.7 grid so NW seed and Spending get more room than Horizon, dropped the BigNumber font from text-2xl to text-xl, and tightened prefix/suffix padding to claw back digits. Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
676 lines
26 KiB
TypeScript
676 lines
26 KiB
TypeScript
/**
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* What-If — interactive Monte Carlo. Compact form on the left, fan
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* chart on the right. Hits POST /simulate (no DB write); ~1-3s for 5k
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* paths.
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*
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* Layout: anchor numbers (NW / spend / horizon) up top; plan (where /
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* how / when) and returns model in compact cards; advanced knobs
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* folded away. Hints live in ⓘ popovers, not always-visible
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* paragraphs, so the form fits on a typical desktop viewport.
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*
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* Allocation is hardcoded to 100% stocks at the API layer — the user
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* is single-allocation, so the glide-path knob was noise. See
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* `api/simulate.py::_project`.
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*/
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import { useMutation, useQuery, useQueryClient } from '@tanstack/react-query';
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import { useEffect, useState } from 'react';
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import { useNavigate } from 'react-router-dom';
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import { api, type SimulateRequest, type SimulateResult } from '@/api/client';
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import { FanChart } from '@/components/FanChart';
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import { InfoTip } from '@/components/InfoTip';
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import { SegmentedControl, type SegmentedOption } from '@/components/SegmentedControl';
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import { gbp, pct } from '@/lib/format';
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const JURISDICTIONS = ['uk', 'cyprus', 'bulgaria', 'malaysia', 'thailand', 'uae', 'nomad'];
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type Strategy = 'trinity' | 'guyton_klinger' | 'vpw' | 'vpw_floor' | 'custom';
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type ReturnsMode = 'shiller' | 'manual' | 'wealthfolio';
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const STRATEGY_OPTIONS: ReadonlyArray<SegmentedOption<Strategy>> = [
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{ value: 'trinity', label: 'Trinity' },
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{ value: 'guyton_klinger', label: 'Guyton-Klinger' },
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{ value: 'vpw', label: 'VPW' },
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{ value: 'vpw_floor', label: 'VPW + floor' },
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{ value: 'custom', label: 'Custom' },
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];
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const RETURNS_OPTIONS: ReadonlyArray<SegmentedOption<ReturnsMode>> = [
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{ value: 'shiller', label: 'Historical' },
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{ value: 'manual', label: 'Manual %' },
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{ value: 'wealthfolio', label: 'Wealthfolio' },
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];
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const STRATEGY_NOTES: Record<Strategy, string> = {
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trinity:
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'Withdraw your "Annual spending" amount in year 1, then keep that real-£ amount fixed. Simple Trinity-style — never adapts to market crashes.',
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guyton_klinger:
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'Spending in year 1, then guardrails: cut 10% if implied withdrawal rate exceeds 120% of starting (and >15y left), raise 10% if it drops below 80%. Adapts to markets.',
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vpw: 'Variable Percentage Withdrawal — each year, withdraw a percentage based on years left and expected real return. Ignores "Annual spending"; algorithmic. Mathematically can\'t fail, but income swings can be wide.',
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vpw_floor:
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'VPW with a hard real-£ floor: never withdraw less than the floor, even if VPW says you should. Trades guaranteed lifestyle against ruin risk in bad sequences.',
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custom:
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'Pick everything: initial spending (above), an annual real-£ adjustment (e.g. -0.5%/yr to spend less with age), and an optional drawdown guardrail.',
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};
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const RETURNS_NOTES: Record<ReturnsMode, string> = {
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shiller:
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'Block-bootstrap of US historical real returns (Shiller 1871+). Broadest regime coverage — includes 1929/1973/2000/2008-style bad sequences. Best default for stress-testing.',
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manual:
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'Every year, every path returns the % you type. Deterministic — no fan, no volatility. Useful for sanity checks ("what if my real return is exactly 5%?").',
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wealthfolio:
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'Block-bootstrap of your actual blended portfolio returns from wealthfolio_sync (~6 years, 2020-present). Reflects your real account mix but biased to the recent regime.',
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};
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const JURISDICTION_NOTES: Record<string, string> = {
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uk: 'UK 2026/27 PAYE + NI + CGT + dividend rules. Personal allowance tapers above £100k; pension withdrawals 25% tax-free.',
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cyprus:
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'Cyprus 60-day non-dom: 17-year exemption on foreign dividends + interest. 2.65% GeSY healthcare levy capped at €180k.',
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bulgaria: 'Flat 10% on worldwide income. EU/EEA capital gains exempt (we apply 10% conservatively).',
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malaysia: 'Foreign-sourced income exempt through 2036. Effective 0% on a typical retiree withdrawal.',
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thailand: 'Foreign-sourced income exempt (v1; the 2024 remittance rule is deferred in this model).',
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uae: 'No personal income tax, no levy. Effective 0%.',
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nomad: 'Tax-free baseline + a 1% regulatory-risk premium to hedge against OECD/CRS rules tightening.',
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};
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const DEFAULTS: SimulateRequest = {
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jurisdiction: 'cyprus',
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strategy: 'guyton_klinger',
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leave_uk_year: 2,
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spending_gbp: '60000',
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nw_seed_gbp: '1500000',
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savings_per_year_gbp: '0',
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horizon_years: 60,
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floor_gbp: null,
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n_paths: 5000,
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seed: 42,
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returns_mode: 'shiller',
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manual_real_return_pct: '0.046',
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annual_real_adjust_pct: '0',
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guardrail_threshold_pct: null,
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guardrail_cut_pct: '0.10',
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};
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export function WhatIf() {
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const [form, setForm] = useState<SimulateRequest>(DEFAULTS);
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const [nwAutoFilled, setNwAutoFilled] = useState(false);
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const navigate = useNavigate();
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const qc = useQueryClient();
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// Pre-fill NW seed from the latest Wealthfolio snapshot the first
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// time it loads, so opening /what-if always starts from real numbers.
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// The user can still edit; we won't clobber their input on later refetches.
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const nw = useQuery({ queryKey: ['networth', 'current'], queryFn: api.networth.current });
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useEffect(() => {
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if (nwAutoFilled || !nw.data || nw.data.accounts.length === 0) return;
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const rounded = String(Math.round(Number(nw.data.total_gbp)));
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setForm((f) => ({ ...f, nw_seed_gbp: rounded }));
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setNwAutoFilled(true);
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}, [nw.data, nwAutoFilled]);
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const sim = useMutation({
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mutationFn: (req: SimulateRequest) => api.simulate(req),
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});
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const save = useMutation({
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mutationFn: (name: string) =>
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api.scenarios.create({
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name,
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jurisdiction: form.jurisdiction,
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strategy: form.strategy,
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leave_uk_year: form.leave_uk_year,
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glide_path: 'static_60_40',
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spending_gbp: form.spending_gbp,
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nw_seed_gbp: form.nw_seed_gbp,
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savings_per_year_gbp: form.savings_per_year_gbp,
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horizon_years: form.horizon_years,
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}),
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onSuccess: (s) => {
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qc.invalidateQueries({ queryKey: ['scenarios'] });
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navigate(`/scenarios/${s.id}`);
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},
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});
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const onSubmit = (e: React.FormEvent) => {
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e.preventDefault();
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const isCustom = form.strategy === 'custom';
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sim.mutate({
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...form,
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floor_gbp: form.strategy === 'vpw_floor' ? form.floor_gbp : null,
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manual_real_return_pct:
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form.returns_mode === 'manual' ? form.manual_real_return_pct : null,
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annual_real_adjust_pct: isCustom ? form.annual_real_adjust_pct : '0',
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guardrail_threshold_pct: isCustom ? form.guardrail_threshold_pct : null,
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guardrail_cut_pct: isCustom ? form.guardrail_cut_pct : '0.10',
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});
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};
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const onSaveAs = () => {
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const suggested = `${form.jurisdiction}-${form.strategy}-leave-y${form.leave_uk_year}`;
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const name = prompt('Save as scenario — name:', suggested);
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if (!name?.trim()) return;
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save.mutate(name.trim());
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};
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const update = <K extends keyof SimulateRequest>(key: K, value: SimulateRequest[K]) =>
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setForm((f) => ({ ...f, [key]: value }));
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const strategy = form.strategy as Strategy;
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const returnsMode = (form.returns_mode ?? 'shiller') as ReturnsMode;
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return (
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<section className="space-y-6">
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<header>
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<h1 className="text-3xl font-semibold tracking-tight">What if…</h1>
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<p className="text-sm text-slate-500">
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Run a single Monte Carlo against the engine. No data persisted. 100% stocks.
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</p>
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</header>
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<div className="grid grid-cols-1 lg:grid-cols-[480px_1fr] gap-6 items-start">
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<form onSubmit={onSubmit} className="space-y-4 sticky top-4">
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<AnchorNumbers form={form} update={update} />
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<PlanCard form={form} update={update} strategy={strategy} />
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<ReturnsCard form={form} update={update} returnsMode={returnsMode} />
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<AdvancedCard form={form} update={update} />
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<button
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type="submit"
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disabled={sim.isPending}
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className="w-full rounded-lg bg-slate-900 text-white text-sm font-semibold px-4 py-3 hover:bg-slate-800 disabled:opacity-60 disabled:cursor-not-allowed shadow-sm"
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>
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{sim.isPending ? 'Running…' : 'Run simulation'}
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</button>
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</form>
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<div className="space-y-4 min-w-0">
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{sim.isError && (
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<div className="rounded-md border border-red-200 bg-red-50 p-4 text-red-800 text-sm">
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{String((sim.error as Error)?.message ?? sim.error)}
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</div>
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)}
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{!sim.data && !sim.isPending && !sim.isError && (
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<div className="rounded-lg border border-slate-200 bg-white p-12 text-center text-slate-500">
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Set parameters on the left and run a simulation.
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</div>
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)}
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{sim.isPending && (
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<div className="rounded-lg border border-slate-200 bg-white p-12 text-center text-slate-500">
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Running Monte Carlo…
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</div>
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)}
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{sim.data && (
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<>
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<Results result={sim.data} horizon={form.horizon_years ?? 60} />
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<div className="flex items-center gap-3">
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<button
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type="button"
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onClick={onSaveAs}
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disabled={save.isPending}
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className="rounded-md border border-slate-300 bg-white text-sm px-4 py-2 hover:bg-slate-50 disabled:opacity-60"
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>
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{save.isPending ? 'Saving…' : 'Save as scenario'}
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</button>
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{save.isError && (
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<span className="text-xs text-red-700">
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{String((save.error as Error)?.message ?? save.error)}
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</span>
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)}
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</div>
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</>
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)}
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<AboutTheModel />
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</div>
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</div>
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</section>
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);
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}
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// ── Sections ─────────────────────────────────────────────────────────
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function AnchorNumbers({
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form,
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update,
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}: {
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form: SimulateRequest;
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update: <K extends keyof SimulateRequest>(k: K, v: SimulateRequest[K]) => void;
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}) {
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return (
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<div className="rounded-lg border border-slate-200 bg-white p-5 shadow-sm">
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<div className="grid grid-cols-[1.4fr_1.2fr_0.7fr] gap-3">
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<BigNumber
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label="NW seed"
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prefix="£"
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value={form.nw_seed_gbp}
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onChange={(v) => update('nw_seed_gbp', v)}
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/>
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<BigNumber
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label="Annual spending"
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prefix="£"
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value={form.spending_gbp}
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onChange={(v) => update('spending_gbp', v)}
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/>
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<BigNumber
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label="Horizon"
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suffix="yrs"
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value={String(form.horizon_years ?? 60)}
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onChange={(v) => update('horizon_years', clampInt(v, 5, 100))}
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step={1}
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/>
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</div>
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</div>
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);
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}
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function PlanCard({
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form,
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update,
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strategy,
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}: {
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form: SimulateRequest;
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update: <K extends keyof SimulateRequest>(k: K, v: SimulateRequest[K]) => void;
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strategy: Strategy;
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}) {
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return (
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<div className="rounded-lg border border-slate-200 bg-white p-4 shadow-sm space-y-4">
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<div className="grid grid-cols-2 gap-3">
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<div>
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<SmallLabel
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text="Jurisdiction"
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tip={JURISDICTION_NOTES[form.jurisdiction]}
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/>
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<select
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value={form.jurisdiction}
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onChange={(e) => update('jurisdiction', e.target.value)}
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className="mt-1 w-full rounded-md border border-slate-300 bg-white px-3 py-2 text-sm focus:outline-none focus:ring-2 focus:ring-slate-400"
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>
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{JURISDICTIONS.map((j) => (
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<option key={j} value={j}>
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{j}
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</option>
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))}
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</select>
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</div>
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<div>
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<SmallLabel text="Years until leaving UK" />
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<input
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type="number"
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value={form.leave_uk_year}
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min={0}
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max={60}
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onChange={(e) => update('leave_uk_year', clampInt(e.target.value, 0, 60))}
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className="mt-1 w-full rounded-md border border-slate-300 bg-white px-3 py-2 text-sm tabular-nums focus:outline-none focus:ring-2 focus:ring-slate-400"
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/>
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</div>
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</div>
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<div>
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<SmallLabel text="Strategy" tip={STRATEGY_NOTES[strategy]} />
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<div className="mt-1">
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<SegmentedControl<Strategy>
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value={strategy}
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onChange={(v) => update('strategy', v)}
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options={STRATEGY_OPTIONS}
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size="sm"
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/>
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</div>
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</div>
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{strategy === 'vpw_floor' && (
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<div>
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<SmallLabel
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text="Floor (£/yr)"
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tip="Hard minimum withdrawal — VPW never dips below this even when the schedule says it should."
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/>
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<input
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type="number"
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value={Number(form.floor_gbp ?? 40000)}
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min={0}
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onChange={(e) => update('floor_gbp', e.target.value)}
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className="mt-1 w-full rounded-md border border-slate-300 bg-white px-3 py-2 text-sm tabular-nums focus:outline-none focus:ring-2 focus:ring-slate-400"
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/>
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</div>
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)}
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{strategy === 'custom' && (
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<div className="rounded-md bg-slate-50 border border-slate-200 p-3 grid grid-cols-3 gap-3">
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<div>
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<SmallLabel
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text="Real adjust %/yr"
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tip="0 = constant real £ (Trinity shape). Positive grows spending each year (e.g. 0.02 = +2%/yr for healthcare). Negative shrinks (e.g. -0.005 to slow down with age)."
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/>
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<input
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type="number"
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value={form.annual_real_adjust_pct ?? '0'}
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step="0.001"
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min={-0.1}
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max={0.1}
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onChange={(e) => update('annual_real_adjust_pct', e.target.value)}
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className="mt-1 w-full rounded-md border border-slate-300 bg-white px-2 py-1.5 text-xs tabular-nums focus:outline-none focus:ring-2 focus:ring-slate-400"
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/>
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</div>
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<div>
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<SmallLabel
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text="Guardrail trigger"
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tip="Fraction of starting NW that triggers a spending cut. e.g. 0.80 = cut once portfolio falls below 80% of seed. Leave blank to disable."
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/>
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<input
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type="number"
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value={form.guardrail_threshold_pct ?? ''}
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step="0.05"
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min={0}
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max={1}
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placeholder="(off)"
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onChange={(e) =>
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update('guardrail_threshold_pct', e.target.value === '' ? null : e.target.value)
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}
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className="mt-1 w-full rounded-md border border-slate-300 bg-white px-2 py-1.5 text-xs tabular-nums focus:outline-none focus:ring-2 focus:ring-slate-400"
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/>
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</div>
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<div>
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<SmallLabel
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text="Guardrail cut"
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tip="Fraction by which to cut last year's withdrawal each triggered year. e.g. 0.10 = -10%."
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/>
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<input
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type="number"
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value={form.guardrail_cut_pct ?? '0.10'}
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step="0.05"
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min={0}
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max={1}
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onChange={(e) => update('guardrail_cut_pct', e.target.value)}
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className="mt-1 w-full rounded-md border border-slate-300 bg-white px-2 py-1.5 text-xs tabular-nums focus:outline-none focus:ring-2 focus:ring-slate-400"
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/>
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</div>
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</div>
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)}
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</div>
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);
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}
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function ReturnsCard({
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form,
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update,
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returnsMode,
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}: {
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form: SimulateRequest;
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update: <K extends keyof SimulateRequest>(k: K, v: SimulateRequest[K]) => void;
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returnsMode: ReturnsMode;
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}) {
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return (
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<div className="rounded-lg border border-slate-200 bg-white p-4 shadow-sm">
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<SmallLabel text="Returns model" tip={RETURNS_NOTES[returnsMode]} />
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<div className="mt-1 flex flex-wrap items-center gap-3">
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<SegmentedControl<ReturnsMode>
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|
value={returnsMode}
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onChange={(v) => update('returns_mode', v)}
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options={RETURNS_OPTIONS}
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size="sm"
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/>
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{returnsMode === 'manual' && (
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<label className="flex items-center gap-2 text-xs text-slate-600">
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<input
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type="number"
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value={form.manual_real_return_pct ?? '0.046'}
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step="0.001"
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min={-0.5}
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max={1}
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onChange={(e) => update('manual_real_return_pct', e.target.value)}
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className="w-24 rounded-md border border-slate-300 bg-white px-2 py-1.5 text-xs tabular-nums focus:outline-none focus:ring-2 focus:ring-slate-400"
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/>
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<span>real / yr (e.g. 0.046 = 4.6%)</span>
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</label>
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)}
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</div>
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</div>
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);
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}
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function AdvancedCard({
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form,
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update,
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}: {
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form: SimulateRequest;
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update: <K extends keyof SimulateRequest>(k: K, v: SimulateRequest[K]) => void;
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}) {
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return (
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<details className="rounded-lg border border-slate-200 bg-white shadow-sm group">
|
|
<summary className="cursor-pointer select-none px-4 py-3 text-sm font-medium text-slate-700 flex items-center justify-between hover:bg-slate-50 rounded-lg">
|
|
<span>Advanced</span>
|
|
<span className="text-xs text-slate-400 group-open:rotate-180 transition-transform">▾</span>
|
|
</summary>
|
|
<div className="px-4 pb-4 pt-1 grid grid-cols-3 gap-3">
|
|
<div>
|
|
<SmallLabel
|
|
text="Annual savings"
|
|
tip="Real-£ added each year (e.g. while still working). 0 = pure decumulation."
|
|
/>
|
|
<input
|
|
type="number"
|
|
value={Number(form.savings_per_year_gbp ?? 0)}
|
|
min={0}
|
|
onChange={(e) => update('savings_per_year_gbp', e.target.value)}
|
|
className="mt-1 w-full rounded-md border border-slate-300 bg-white px-2 py-1.5 text-sm tabular-nums focus:outline-none focus:ring-2 focus:ring-slate-400"
|
|
/>
|
|
</div>
|
|
<div>
|
|
<SmallLabel
|
|
text="MC paths"
|
|
tip="More paths = tighter percentile estimates but slower. 5k is a sweet spot; 50k for final."
|
|
/>
|
|
<input
|
|
type="number"
|
|
value={form.n_paths ?? 5000}
|
|
min={100}
|
|
max={50000}
|
|
step={100}
|
|
onChange={(e) => update('n_paths', clampInt(e.target.value, 100, 50000))}
|
|
className="mt-1 w-full rounded-md border border-slate-300 bg-white px-2 py-1.5 text-sm tabular-nums focus:outline-none focus:ring-2 focus:ring-slate-400"
|
|
/>
|
|
</div>
|
|
<div>
|
|
<SmallLabel text="Seed" tip="Same seed = same fan. Change to verify a result is robust." />
|
|
<input
|
|
type="number"
|
|
value={form.seed ?? 42}
|
|
onChange={(e) => update('seed', clampInt(e.target.value, 0, 999999))}
|
|
className="mt-1 w-full rounded-md border border-slate-300 bg-white px-2 py-1.5 text-sm tabular-nums focus:outline-none focus:ring-2 focus:ring-slate-400"
|
|
/>
|
|
</div>
|
|
</div>
|
|
</details>
|
|
);
|
|
}
|
|
|
|
// ── Primitives ───────────────────────────────────────────────────────
|
|
|
|
function SmallLabel({ text, tip }: { text: string; tip?: string }) {
|
|
return (
|
|
<div className="flex items-center gap-1.5">
|
|
<span className="text-[11px] uppercase tracking-wide text-slate-500 font-medium">{text}</span>
|
|
{tip && <InfoTip text={tip} label={text} />}
|
|
</div>
|
|
);
|
|
}
|
|
|
|
function BigNumber({
|
|
label,
|
|
value,
|
|
onChange,
|
|
prefix,
|
|
suffix,
|
|
step = 1,
|
|
}: {
|
|
label: string;
|
|
value: string;
|
|
onChange: (v: string) => void;
|
|
prefix?: string;
|
|
suffix?: string;
|
|
step?: number;
|
|
}) {
|
|
return (
|
|
<label className="block min-w-0">
|
|
<span className="text-[11px] uppercase tracking-wide text-slate-500 font-medium">
|
|
{label}
|
|
</span>
|
|
<div className="mt-1 relative">
|
|
{prefix && (
|
|
<span className="absolute left-2.5 top-1/2 -translate-y-1/2 text-slate-400 text-base pointer-events-none">
|
|
{prefix}
|
|
</span>
|
|
)}
|
|
<input
|
|
type="number"
|
|
value={value}
|
|
step={step}
|
|
min={0}
|
|
onChange={(e) => onChange(e.target.value)}
|
|
className={`w-full rounded-md border border-slate-300 bg-white py-2 text-xl font-semibold tabular-nums focus:outline-none focus:ring-2 focus:ring-slate-400 ${
|
|
prefix ? 'pl-6' : 'pl-2.5'
|
|
} ${suffix ? 'pr-9' : 'pr-2.5'}`}
|
|
/>
|
|
{suffix && (
|
|
<span className="absolute right-2.5 top-1/2 -translate-y-1/2 text-slate-400 text-xs pointer-events-none">
|
|
{suffix}
|
|
</span>
|
|
)}
|
|
</div>
|
|
</label>
|
|
);
|
|
}
|
|
|
|
function clampInt(raw: string, min: number, max: number): number {
|
|
const n = Math.round(Number(raw));
|
|
if (!Number.isFinite(n)) return min;
|
|
return Math.min(max, Math.max(min, n));
|
|
}
|
|
|
|
// ── Result panel + about ─────────────────────────────────────────────
|
|
|
|
function AboutTheModel() {
|
|
return (
|
|
<details className="rounded-lg border border-slate-200 bg-white p-5 group">
|
|
<summary className="cursor-pointer text-base font-semibold flex items-center justify-between">
|
|
<span>About the model</span>
|
|
<span className="text-xs text-slate-500 group-open:hidden">Click to expand</span>
|
|
</summary>
|
|
<div className="mt-4 space-y-5 text-sm text-slate-700">
|
|
<Section title="Withdrawal strategies">
|
|
<Term name="Trinity 4%">{STRATEGY_NOTES.trinity}</Term>
|
|
<Term name="Guyton-Klinger guardrails">{STRATEGY_NOTES.guyton_klinger}</Term>
|
|
<Term name="VPW">{STRATEGY_NOTES.vpw}</Term>
|
|
<Term name="VPW + floor">{STRATEGY_NOTES.vpw_floor}</Term>
|
|
<Term name="Custom spending plan">{STRATEGY_NOTES.custom}</Term>
|
|
</Section>
|
|
<Section title="Tax jurisdictions">
|
|
<Term name="UK">{JURISDICTION_NOTES.uk}</Term>
|
|
<Term name="Cyprus">{JURISDICTION_NOTES.cyprus}</Term>
|
|
<Term name="Bulgaria">{JURISDICTION_NOTES.bulgaria}</Term>
|
|
<Term name="Malaysia">{JURISDICTION_NOTES.malaysia}</Term>
|
|
<Term name="Thailand">{JURISDICTION_NOTES.thailand}</Term>
|
|
<Term name="UAE">{JURISDICTION_NOTES.uae}</Term>
|
|
<Term name="Nomad (no fixed residency)">{JURISDICTION_NOTES.nomad}</Term>
|
|
</Section>
|
|
<Section title="How the engine treats tax">
|
|
<p>
|
|
Each year the strategy proposes a real-£ withdrawal <code>w</code>; the chosen
|
|
jurisdiction's tax engine computes <code>tax(w)</code>; the portfolio drops by
|
|
<code> w + tax(w)</code>. Higher-tax jurisdictions therefore drain the portfolio
|
|
faster and lower the success rate — switching jurisdiction visibly moves the fan,
|
|
not just the lifetime-tax cell.
|
|
</p>
|
|
</Section>
|
|
<Section title="Returns model">
|
|
<Term name="Historical (Shiller 1871+)">{RETURNS_NOTES.shiller}</Term>
|
|
<Term name="Manual real return">{RETURNS_NOTES.manual}</Term>
|
|
<Term name="My Wealthfolio history">{RETURNS_NOTES.wealthfolio}</Term>
|
|
<p className="pt-1">
|
|
Each path resamples blocks independently so sequence-of-returns risk is preserved.
|
|
Long-run benchmarks for context: 60/40 real ≈ 4.6%; equities ~9.5% nominal /
|
|
17% volatility; bonds ~5%/8%.
|
|
</p>
|
|
</Section>
|
|
<Section title="Allocation">
|
|
<p>
|
|
All What-If runs use 100% stocks. The glide-path knob was removed in May 2026
|
|
— the user is single-allocation in real life, so simulating 60/40 mixes was noise.
|
|
Persisted Cartesian scenarios still carry their own glide string.
|
|
</p>
|
|
</Section>
|
|
<Section title="Success rate">
|
|
<p>
|
|
A path counts as a success if the portfolio stays positive through every interim
|
|
year. The very last year-end is excluded because VPW deliberately drains to ~0
|
|
at the horizon by construction.
|
|
</p>
|
|
</Section>
|
|
</div>
|
|
</details>
|
|
);
|
|
}
|
|
|
|
function Section({ title, children }: { title: string; children: React.ReactNode }) {
|
|
return (
|
|
<div>
|
|
<h3 className="text-sm font-semibold text-slate-900 mb-2">{title}</h3>
|
|
<div className="space-y-2">{children}</div>
|
|
</div>
|
|
);
|
|
}
|
|
|
|
function Term({ name, children }: { name: string; children: React.ReactNode }) {
|
|
return (
|
|
<div>
|
|
<span className="font-medium">{name}.</span>{' '}
|
|
<span className="text-slate-600">{children}</span>
|
|
</div>
|
|
);
|
|
}
|
|
|
|
function Results({ result, horizon }: { result: SimulateResult; horizon: number }) {
|
|
return (
|
|
<>
|
|
<div className="grid grid-cols-2 md:grid-cols-4 gap-3">
|
|
<Stat label="Success rate" value={pct(result.success_rate)} accent />
|
|
<Stat label="Median ending NW" value={gbp(result.p50_ending_gbp)} />
|
|
<Stat label="P10 ending" value={gbp(result.p10_ending_gbp)} />
|
|
<Stat label="P90 ending" value={gbp(result.p90_ending_gbp)} />
|
|
<Stat label="Median lifetime tax" value={gbp(result.median_lifetime_tax_gbp)} />
|
|
<Stat label="Median years to ruin" value={result.median_years_to_ruin ?? 'never'} />
|
|
<Stat label="Horizon" value={`${horizon} years`} />
|
|
<Stat label="Engine time" value={`${result.elapsed_seconds}s`} />
|
|
</div>
|
|
<div className="rounded-lg border border-slate-200 bg-white p-5">
|
|
<h2 className="text-lg font-semibold mb-2">Portfolio fan</h2>
|
|
<FanChart yearly={result.yearly} height={420} showWithdrawal />
|
|
</div>
|
|
</>
|
|
);
|
|
}
|
|
|
|
function Stat({
|
|
label,
|
|
value,
|
|
accent,
|
|
}: {
|
|
label: string;
|
|
value: string | number;
|
|
accent?: boolean;
|
|
}) {
|
|
return (
|
|
<div className="rounded-md border border-slate-200 bg-white p-3">
|
|
<div className="text-xs uppercase tracking-wide text-slate-500">{label}</div>
|
|
<div
|
|
className={`text-xl font-semibold tabular-nums mt-1 ${
|
|
accent ? 'text-emerald-700' : ''
|
|
}`}
|
|
>
|
|
{value}
|
|
</div>
|
|
</div>
|
|
);
|
|
}
|