{
  "version": "2026.1",
  "generated_at": "2026-07-22",
  "generated_by": "backend/tools/withdrawal_study_dump.c (JSONL) -> scripts/gen_withdrawal_order_study.mjs",
  "study": "withdrawal-order-tax-2026",
  "engine": "monte_carlo.c run_monte_carlo_tax_aware (per-year single-year tax-cost order vs independent trad-first baseline)",
  "tax_year": 2026,
  "method": {
    "num_sims": 4000,
    "seed": 4242,
    "sampling": "seeded pseudo-random (use_qmc=0; env-robust, no Sobol dependency)",
    "allocation": [
      0.4,
      0.15,
      0.35,
      0.05,
      0.05
    ],
    "asset_classes": [
      "us_equity",
      "intl_equity",
      "bonds",
      "real_estate",
      "cash"
    ],
    "inflation_rate": 0.025,
    "headline_statistic": "paired_median_savings = median over paths of (trad_first_i - tax_aware_i); p10-p90 band of that same per-path difference",
    "baseline": "independent traditional-first simulation on its own balances/ledger sharing the market path (common random numbers)",
    "per_lot_accounting": "HIFO, short/long-term character tracked"
  },
  "verification": "The tax-aware per-year order comes from optimize_withdrawal, cross-checked against an independent grid replica and a hand-computed 2026 federal-tax anchor by backend/tools/withdrawal_verify.c. Every figure here is emitted directly by the engine via backend/tools/withdrawal_study_dump.c.",
  "determinism": [
    {
      "type": "determinism",
      "persona": "corridor_62_balanced_fl",
      "paired_savings_diff": 0,
      "lifetime_tax_aware_diff": 0,
      "lifetime_trad_first_diff": 0,
      "success_rate_diff": 0,
      "identical": true
    }
  ],
  "headline": {
    "helps_representative_persona": "corridor_62_balanced_fl",
    "helps_representative_median": 28806.77,
    "helps_representative_p10": 8180.28,
    "helps_representative_p90": 41535.03,
    "backfires_representative_persona": "straddle_70_trad_heavy_ca",
    "backfires_representative_median": -10613.44,
    "backfires_representative_p10": -22375.67,
    "backfires_representative_p90": 2312.49,
    "n_helps": 5,
    "n_backfires": 2
  },
  "personas": [
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        "case_class": "corridor",
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        "bal_roth": 200000,
        "bal_taxable": 300000,
        "total_balance": 1000000,
        "annual_withdrawal": 60000,
        "social_security_monthly": 2500,
        "social_security_start_age": 67
      },
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        "success_rate": 0.99925,
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    },
    {
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}