Frequently Asked Questions
What does this tool actually compare?
It takes the payroll taxes a worker would pay into Social Security (the 10.6% OASI retirement portion) and models those same dollars two ways: paid into Social Security for the statutory benefit, or invested in a defined-contribution account and drawn down in retirement. Both are computed under identical inputs. See How the Model Works.
Is this financial advice?
No. It is an educational tool. It does not know your situation, never connects to your SSA record or any financial account, and every figure is computed from values you enter. For decisions about your own retirement, consult a qualified professional. For your real benefit number, use ssa.gov/myaccount.
Does the model always say "invest it instead"?
No — and this is the most important thing to understand about it. As of the July 2026 build, under conservative assumptions (payroll contributions held entirely in Treasuries or bonds), Social Security won, and it was not close. The defined-contribution advantage was large only with equity exposure. See Headline Results.
Why does equity exposure matter so much?
In the July 2026 model the gap between a bond posture and even a conservative equity posture was about a factor of six at the median earner, with essentially nothing in between — what we call the "equity cliff." The single decision that determined whether the DC path beat Social Security was whether the money touched equities at all, more than income, retirement age, or lifespan.
Doesn't a 4% withdrawal rule stack the deck by leaving a big balance?
It is a fair objection, and the model answers it from both directions. Forced to pay Social Security's exact income, the glidepath still left an eight-figure estate while a bond portfolio went bankrupt. Forced to spend down to zero like Social Security, the glidepath paid three to seven times the monthly income. The withdrawal-rule analysis walks through both tests.
Does the advantage really grow for younger generations?
No — we retracted that claim. An earlier version of the study reported it, but it was an artifact of two engine defects. On the corrected engine the benefit formula is cohort-invariant; differences across birth years reflect each cohort's market-history window, not the policy. See Corrections & Retractions.
Why do you publish your own mistakes?
Because a tool that can only ever produce one answer is an argument, not a model. In July 2026 we audited our own engine, found four defects, fixed them, and formally retracted five earlier headline claims. We think that is the most credible thing a model can do. See The Methods Audit.
What are the model's stated limitations?
Social Security's disability and survivor benefits are not included in the comparison. Taxes on DC distributions and Medicare premium interactions are not modeled. Market return series are historical — the future may differ. See How the Model Works for the full list.
Where does the historical return data come from?
From per-tier return series summarized by geometric mean — the correct compounding measure. The series was corrected during the July 2026 audit; the bond series in particular was aligned with the U.S. Aggregate record. See Data Sources & Citations.
Can I challenge the methodology?
Yes — and we welcome it. A model built to be checked needs checkers. Use the Contact page. If you find something wrong, it will end up in Corrections & Retractions.
Educational purposes only — not financial, tax, or investment advice. Past performance does not guarantee future results.