diff --git a/src/data/selectors.js b/src/data/selectors.js
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+// src/data/selectors.js
+// Pure analytics derived from the live store arrays. No React; no imports from mockStore.
+// Callers pass the arrays they already have from useMockStore(); these functions never read context.
+// This single-source-of-truth is what guarantees dashboards can never drift from the records:
+// every KPI is computed here, and the same function feeds every screen + the reconciliation checks.
+
+// Open pre-sale pipeline stages, in funnel order. Won/in-progress/complete are projects, not pipeline.
+export const PRESALE_STAGES = ['kc_new', 'kc_contacted', 'kc_appt', 'kc_estimate'];
+
+const sum = (arr, f) => arr.reduce((s, x) => s + (f(x) || 0), 0);
+const isPresale = (l) => PRESALE_STAGES.includes(l.columnId);
+
+// Funnel: count + $ value at each open stage.
+export function pipelineFunnel(kanbanLeads = []) {
+  return PRESALE_STAGES.map((stage) => {
+    const leads = kanbanLeads.filter((l) => l.columnId === stage);
+    return { stage, count: leads.length, value: sum(leads, (l) => l.value) };
+  });
+}
+
+// Total open pipeline $ = Σ value of pre-sale leads.
+export function pipelineValue(kanbanLeads = []) {
+  return sum(kanbanLeads.filter(isPresale), (l) => l.value);
+}
+
+// Win rate % over DECIDED leads: won (has projectId) vs lost (kc_lost | outcome 'lost').
+export function winRate(kanbanLeads = []) {
+  const won = kanbanLeads.filter((l) => !!l.projectId).length;
+  const lost = kanbanLeads.filter((l) => l.columnId === 'kc_lost' || l.outcome === 'lost').length;
+  const decided = won + lost;
+  return { won, lost, decided, rate: decided ? Math.round((won / decided) * 100) : 0 };
+}
+
+// Revenue recognized = Σ client payments received (paymentSchedule status 'paid'); cost = Σ actualCost.
+export function revenueSummary(projects = []) {
+  const revenue = sum(projects, (p) =>
+    sum((p.paymentSchedule || []).filter((ps) => ps.status === 'paid'), (ps) => ps.amount));
+  const cost = sum(projects, (p) => Number(p.actualCost ?? p.spent ?? 0));
+  const commissions = sum(projects, (p) => Number(p.commission || 0));
+  return { revenue, cost, grossProfit: revenue - cost, commissions, netProfit: revenue - cost - commissions };
+}
+
+// Commission grouped by the project's sales rep. resolvePerson(id)->{name} optional, for display.
+export function commissionByRep(projects = [], resolvePerson) {
+  const byRep = {};
+  for (const p of projects) {
+    const repId = p.salesRepId
+      || (p.teamMembers || []).find((t) => /Sales|Estimator/i.test(t.jobRole || ''))?.userId;
+    if (!repId) continue;
+    byRep[repId] = (byRep[repId] || 0) + Number(p.commission || 0);
+  }
+  return Object.entries(byRep)
+    .map(([repId, total]) => ({ repId, name: resolvePerson?.(repId)?.name || repId, total }))
+    .sort((a, b) => b.total - a.total);
+}
+
+// Subcontractor performance: project count + total fees + task count, per sub.
+// tasks = MOCK_SUBCONTRACTOR_TASKS; resolvePerson optional for names.
+export function subcontractorPerformance(projects = [], tasks = [], resolvePerson) {
+  const acc = {};
+  for (const p of projects) {
+    for (const subId of p.subcontractorIds || []) {
+      acc[subId] = acc[subId] || { subId, projects: 0, tasks: 0, fees: 0 };
+      acc[subId].projects += 1;
+    }
+  }
+  for (const t of tasks) {
+    const id = t.subcontractorId;
+    if (!id) continue;
+    acc[id] = acc[id] || { subId: id, projects: 0, tasks: 0, fees: 0 };
+    acc[id].tasks += 1;
+    acc[id].fees += sum(t.fees || [], (f) => f.amount);
+  }
+  return Object.values(acc)
+    .map((r) => ({ ...r, name: resolvePerson?.(r.subId)?.name || r.subId }))
+    .sort((a, b) => b.projects - a.projects);
+}
+
+// Storm attribution: share of pipeline value and recognized revenue traceable to storm-sourced leads.
+export function stormAttribution(kanbanLeads = [], projects = []) {
+  const stormLeadIds = new Set(kanbanLeads.filter((l) => l.stormSource).map((l) => l.id));
+  const stormPipeline = sum(kanbanLeads.filter((l) => isPresale(l) && l.stormSource), (l) => l.value);
+  const totalPipeline = pipelineValue(kanbanLeads);
+  const stormProjects = projects.filter((p) => stormLeadIds.has(p.sourceLeadId));
+  const stormRevenue = revenueSummary(stormProjects).revenue;
+  const totalRevenue = revenueSummary(projects).revenue;
+  return {
+    stormLeadCount: stormLeadIds.size,
+    stormPipeline, totalPipeline,
+    pipelinePct: totalPipeline ? Math.round((stormPipeline / totalPipeline) * 100) : 0,
+    stormRevenue, totalRevenue,
+    revenuePct: totalRevenue ? Math.round((stormRevenue / totalRevenue) * 100) : 0,
+  };
+}