Rules-Based Retirement Math

Systematic Rules for Financial Independence

I build rules-based retirement tools and backtesters to stress-test safe withdrawal rates, track trend-following model portfolios, and protect savings from sequence risk.

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Flagship Model Portfolios & Safe Withdrawal Rates View All Portfolios →
Core Balanced Tier ER_MMA ADVANCED

Regime All-Weather Portfolio

A balanced multi-asset strategy modeled after Ray Dalio's All Weather asset mix, designed to perform well in all economic regimes (inflation, deflation, growth, and recession). Combines equities, bonds, gold, and commodities under systematic trend-following overlays.

Max DD
-6.06%
vs -23.37%
Sortino
1.69
vs 1.01
CAGR
7.18%
vs 6.83%
SPY 30% TLT 40% IEF 15% IAU 7.5% PDBC 7.5%
View Track Record →
Core Balanced Tier ER_MMA ADVANCED

Classic 60/40

The benchmark standard balanced portfolio. Combines 60% global equities with 40% aggregate bonds to provide diversified exposure and a favorable balance between risk and long-term capital growth.

Max DD
-11.06%
vs -34.7%
Sortino
1.31
vs 0.84
CAGR
7.9%
vs 8.4%
SPY 60% AGG 40%
View Track Record →
Aggressive Growth Tier ER_MMA ADVANCED

Aggressive Alpha Momentum

A high-conviction aggressive strategy utilizing a 30% tilt toward 2x leveraged Nasdaq-100 exposure for maximum growth potential. Optimized for high risk-adjusted returns by balancing tactical tech momentum with total U.S. stock market stability.

Max DD
-21.72%
vs -55.13%
Sortino
1.03
vs 0.73
CAGR
13.97%
vs 12.75%
QQQ>QLD 30% VTI 45% RSP 25%
View Track Record →
FIRE RETIREMENT PIPELINE From Wealth Accumulation to Sustainable Decumulation

Instant Financial Independence Calculator

Model Assumptions & Mathematical Framework:
  • Stage 1 (Wealth Accumulation): Assumes a 7.0% annualized real return (compounded annually: $$FV = PV \cdot (1+r)^n + PMT \cdot \left[\frac{(1+r)^n - 1}{r}\right]$$), representing historical US equity real return after inflation. Values reflect purchasing power in today's dollars.
  • Stage 2 (Retirement Decumulation): Evaluates a 30-year retirement horizon under the standard 4.0% Bengen Safe Withdrawal Rate ($40,000/yr per $1,000,000 nest egg). Safe withdrawals step up annually with inflation.
  • Sequence of Returns Risk: In severe market crashes (-35% to -55%), fixed dollar decumulation forces retirees to liquidate assets at steep discounts. Dynamic sequence modeling, variable withdrawal strategies, and trend-following drawdown defenses can be explored in our Interactive Calculators.
Disclaimer: For educational research and scenario planning only. Comprehensive multi-account tax modeling (Roth conversions, IRMAA, capital gains) and variable withdrawal strategies (VWS) are available in our full Interactive Calculators.
STAGE 1: WEALTH ACCUMULATION Grow Your Nest Egg
7.0% Real CAGR
$100,000
$0 $500k $1.0M
$30,000 ($2,500/mo)
$0/yr $75k/yr $150k/yr
15 Years
1 Year 20 Years 40 Years
PROJECTED RETIREMENT NEST EGG
Auto-flows into Stage 2 →
$1,029,774
STAGE 2: DECUMULATION Retirement Cash Flow
$
$100k $2.5M $5.0M
Sustainable Living Budget (Real)
4.00% SWR
$41,191 / yr
Monthly Purchasing Power
$3,433 /mo
Launch Full Monte Carlo Calculators →
LATEST MARKET DISPATCH šŸ“… Aug 1, 2026
$XLK $IGV $XLRE $XLF

Month-End Sector Pulse: Broad Sector Freeze as Tech and Real Estate Rollover

8 out of 11 sectors have ground to a halt, while Tech, Software, and Real Estate are actively rolling over on short-term momentum.

Read Full Dispatch →
PLATFORM FEATURE

Automated Email Alerts & Daily Digests

Get automated daily email alerts whenever model portfolio trend signals flip. Track allocation changes instantly without checking the site manually every day.

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Research Guides

All Research Guides →
Why Maximum Drawdown Dictates Retirement Longevity
Published 2026-08-18

Why Maximum Drawdown Dictates Retirement Longevity

In retirement decumulation, average returns are secondary to tail risk. Here is the math and empirical historical evidence showing how cutting peak drawdowns preserves your nest egg and prevents capital depletion.

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Why Your Bond Choice Can Break the 4% Rule
Published 2026-07-22

Why Your Bond Choice Can Break the 4% Rule

Bengen specified 5-year U.S. Treasuries for a reason. This analysis shows what happens historically when investors substitute other bond types ā€” and how much it matters which bonds you hold.

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Can You Safely Retire on a 100% Stock Portfolio? Trend-Following, SWRs, and the Sequence Risk Trade-Off
Published 2026-07-20

Can You Safely Retire on a 100% Stock Portfolio? Trend-Following, SWRs, and the Sequence Risk Trade-Off

Replicating Bengen's 4% rule with historically accurate intermediate-term Treasuries shows that trend-following allows retirees to hold 100% equity portfolios nearly as safely as a passive 50/50 allocationā€”but combining the two introduces a costly double drag in growth regimes.

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Considering retiring early, but worried about healthcare (ACA) costs?
Published 2026-03-11

Considering retiring early, but worried about healthcare (ACA) costs?

With some financial engineering, you can reduce (and possibly eliminate) the cost of ACA coverage.

Read Guide Watch Video
Defending Your Savings Against Significant Downturns
Published 2026-05-23

Defending Your Savings Against Significant Downturns

What happens if the market doesnā€™t just "dip," but stays down for a decade or more? We explore strategies to safeguard your savings from prolonged stagnation.

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The 4% Rule Is Dead, Here's What's Replaced It
Published 2025-12-18

The 4% Rule Is Dead, Here's What's Replaced It

The 4% rule, which we wrote about in our post regarding Safe Withdrawal Rate, was established back in 1994. Since then, many alternatives have been suggested. We review the major alternatives.

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Frequently Asked Questions

Traditional safe withdrawal rates (like the 4% rule) are constrained by catastrophic sequence-of-returns risk during severe bear markets. When an early retiree must sell equities at steep 40% to 50% drawdowns to fund living expenses, their portfolio suffers irreversible capital depletion. By applying systematic moving-average overlays (such as Excess Return MMA) to exit risk assets during downtrends and hold cash or short-term Treasuries, peak portfolio drawdowns are truncated (e.g. cutting a -34.7% maximum drawdown down to -11.1% on a 60/40 portfolio). Capping crash losses prevents selling at depressed prices, mathematically allowing retirees to sustain a higher baseline safe withdrawal rate (e.g. 4.36% vs. 3.49% on Buy & Hold). Learn more in our guide on Understanding Safe Withdrawal Rates.

Sequence of returns risk refers to the danger of experiencing severe market downturns in the first 5 to 10 years of retirement. If a portfolio drops 40% while paying out annual withdrawals, the remaining capital cannot recover even if the broader market rebounds later. Our historical backtests across rolling 30-year cohorts show that maximum drawdown is the single largest determinant of retirement failure. Truncating drawdown depth protects the principal balance during early decumulation years, preserving the compounding engine needed to fund longevity. Read our empirical analysis on Why Max Drawdown Dictates Retirement Longevity.

Buy-and-Hold passive index portfolios remain 100% invested at all times, enduring 100% of market crashes, multi-year drawdowns, and volatility spikes. AlgorithmicFIRE model portfolios use the same low-cost index ETFs (such as VTI, SPY, QQQ, TLT, AGG) but introduce a systematic, rules-based trend overlay. When price trend signals drop below systematic moving-average thresholds, the strategy shifts the affected sleeve into cash or short-term Treasuries, re-entering only after a verified recovery trend is established. Explore our full catalog of Tactical Model Portfolios.

Our model portfolios are designed specifically for tax efficiency and low turnover, averaging only 2 to 4 allocation shifts per asset sleeve per year. Trend signals are evaluated daily at market close using end-of-day data, and trades are executed at the market open on the subsequent trading day. There is zero intra-day day trading or high-frequency turnover. Subscribers receive automated daily email digests whenever signals flip.

All model simulations are computed dynamically using unadjusted daily dividend-reinvested total return price series from authoritative data sources spanning over 20 years of market history. Backtests rigorously model next-day open transaction execution, conservative trade slippage, fund expense ratios, and historical inflation metrics to provide research-grade accuracy with zero synthesized or forward-looking data. You can model your own custom asset allocations in our Interactive Retirement Calculators.

The Two-Stage FIRE Pipeline connects the savings phase directly to the retirement spending phase in real purchasing power. In Stage 1 (Wealth Accumulation), it compounds current portfolio savings and annual contributions at an annualized 7.0% real CAGR net of inflation ($$FV = PV \cdot (1+r)^n + PMT \cdot \left[\frac{(1+r)^n - 1}{r}\right]$$). The resulting terminal nest egg automatically flows into Stage 2 (Retirement Decumulation), where it stress-tests sustainable annual and monthly living budgets against a 98% historical solvency floor over 30-year market horizons across trend-following strategies versus Buy & Hold.