Decumulation Studio

The Decumulation Studio searches a joint schedule of Roth conversions and account-by-account withdrawals against a user-selected objective (fill a bracket, stay below an IRMAA tier, maximize real terminal wealth, maximize lifetime ACA premium tax credits, or minimize lifetime tax present value). It evaluates the proposed schedule alongside a baseline (no-conversion, naive sequencing) so the tradeoff is explicit.

• Joint conversion and withdrawal schedule by year and account.
• Pluggable objectives covering bracket fill, IRMAA ceiling, ACA credit maximization, lifetime tax PV, and real terminal wealth.
• Per-year multi-cliff explainer: which constraint set bound the optimizer in each year.
• Marginal-cost surface that quantifies how much each extra dollar of conversion or withdrawal would cost across years.
• Year-drill decomposition showing the ordinary marginal, NIIT, LTCG bump, ACA, IRMAA, and state-tax components of the marginal dollar.

• Evaluate decumulation strategies after retirement when conversions and withdrawals interact with Social Security taxation, Medicare IRMAA, ACA subsidy cliffs, RMDs, and Roth 5-year clocks.
• Compare withdrawal orderings (taxable-first, traditional-first, Roth-last) under the same household, return, and inflation assumptions.
• Stress-test a planned schedule against bracket and IRMAA caps and see which years approach which cliffs.

• Plan anchor: start year and horizon years. Every dated rule (RMD, IRMAA y-2 lookback, ACA regime) resolves from the start year.
• Household: the selected household supplies members, accounts, filing status, resident state, ACA inputs, and prior IRMAA MAGI history.
• Assumptions: nominal asset return, inflation rate, and real annual spending.
• Objective: bracket fill, IRMAA tier ceiling, lifetime ACA PTC, lifetime tax PV, or real terminal wealth.
• Withdrawal policy: taxable-first, traditional-first, or Roth-last sequencing.
• Constraint caps: ordinary bracket cap, optional IRMAA tier ceiling, optional LTCG 0% preservation, and optional NIIT prevention.

• Action schedule: conversion and withdrawal amounts by year and account.
• Binding-constraint rows: the cliff or cap that bound each year for the proposed schedule and the baseline.
• Marginal surface: dollar-by-dollar cost of additional conversion or withdrawal pressure across the horizon.
• Year drill: ordinary marginal, LTCG bump, NIIT delta, IRMAA delta (y+2), ACA delta, and state marginal for a chosen year.

• Saved analyses for this tool are private-only. Generic public share links are not registered for Decumulation Studio runs.
• ACA FPL modeling supports contiguous states/DC, Alaska, and Hawaii poverty-guideline tables.
• The optimizer is a bracket-fill heuristic plus a marginal-cost search. It is not a stochastic or globally optimal solver.