$2,500 a month starts at 6% a year.
Does keeping 10% in T-bills make QQQ safer for retirement?
Strategy in short: Hold 90% in QQQ and 10% in three-month T-bills. Take spending from T-bills first and restore 90/10 every 12 months.
Retirement answer: 90% QQQ / 10% T-bills supported more starting spending than Always QQQ: 2.5% versus 2.2% a year funded 30 years in at least 95% of both sets of histories. These are historical thresholds, not recommended spending.
Return comparison: Always QQQ made more money in this backtest. 90% QQQ / 10% T-bills ended with $153,429 and Always QQQ with $166,246.
Growth of $10,000 — logarithmic scale
90% QQQ / 10% T-bills had a deepest fall of 75.4%, compared with 81.1% for Always QQQ.
See what 10% in T-bills actually changed
The T-bill sleeve absorbs part of every fall and gives up part of every rise. Annual rebalancing restores the cushion after QQQ moves.
The allocation was restored on its scheduled rebalance dates. The strategy's deepest fall was 75.4%, compared with 81.1% for Always QQQ.
90% QQQ / 10% T-bills$153,429-75.4% deepest fall
Always QQQ$166,246-81.1% deepest fall
April 1999 through June 2026. Distributions are reinvested. The calculation charges 0.10% of each risky asset bought or sold. There are no withdrawals in this graph. Equal percentage moves take equal vertical space. Past results do not predict future results.
Did the cash cushion support more monthly spending?
By March 2010, Always QQQ had run out while 90% QQQ / 10% T-bills still had $60,215.
Avoiding more of the earlier losses left money available to keep paying withdrawals.
Example: You have $500,000 and need $2,500 a month—6% a year.
The same spending then equaled 65.7% a year.
The portfolio had run out of money.
What funded at least 95% of both history tests?
90% QQQ / 10% T-bills supported a 2.5% starting annual withdrawal for 30 years: 325 ordered starts and 4,757 of 5,000 mixed histories funded every withdrawal.
These are historical thresholds, not recommended spending amounts or a promise of future success.
Test if 90% QQQ / 10% T-bills can fund your early retirement with your own numbers
Enter your portfolio, monthly spending, and how long the money needs to last.
$2,500 a month for 30 years starts at 6.0% of the portfolio each year.
In these backtests, sometimes. Neither strategy funded this early retirement in at least 8 out of 10 histories tested.
327 starting months; the fund's record repeats in order when needed
- 90% QQQ / 10% T-bills
- 252 funded
- Always QQQ
- 247 funded
5,000 histories built from 8–12-year pieces
- 90% QQQ / 10% T-bills
- 3,855 funded
- Always QQQ
- 3,837 funded
A path funded the goal only if it paid every inflation-adjusted monthly withdrawal for 30 years. Results use the nearest 0.1 percentage-point starting withdrawal rate. They reuse one 27-year market record and are not a probability about your future.
How the FIRE calculator works
The calculator applies the portfolio value, monthly withdrawal, and number of years you enter. The first withdrawal occurs before the first month's return, and later withdrawals rise with U.S. inflation. A history counts as funded only if it pays every monthly withdrawal for the full period and finishes above zero.
One result begins at each of the 327 months in the fund record and follows that record forward in order, returning to its first month when more months are needed. The other builds 5,000 longer histories from linked 8-, 10-, and 12-year pieces of the same record. The calculation charges 0.10% whenever QQQ is bought or sold and excludes personal tax.
At every repeated or rearranged join, market signals use the real observations that preceded the incoming historical month. Portfolio value, withdrawals, inflation and strategy state continue without resetting.
Strategy in detail
Hold 90% in QQQ and 10% in three-month T-bills. Take spending from T-bills first and restore 90/10 every 12 months.
A small cash reserve can reduce forced selling during a fall. Its cost is that less of the portfolio participates when QQQ rises.
Can I trust these results?
My evidence-weighted estimate is about 74% that the main effect would persist in a new long market period. That makes the result promising, not dependable enough to treat as a promise.
The direct test covers April 1999 through June 2026. It includes fund distributions, T-bill returns, inflation and the stated trading costs, but it is still one U.S. market record. The longer retirement histories repeat it or link 8–12-year pieces; they test difficult orders, not new historical evidence.
Treat the result as evidence about how the rule behaved, then compare it with simpler alternatives and your own ability to follow it through a bad period.
Methodology details for the nerds
How I ran the return comparison
The test starts with the amount shown on the graph. Each decision uses only information already complete at that month-end. Distributions are reinvested, T-bills earn the published three-month rate, and the calculation charges 0.10% of each risky asset bought or sold.
How I tested retirement withdrawals
The first withdrawal occurs before the first month's return. Spending then rises with U.S. inflation. One panel checks every starting month in order; the other links 5,000 histories from 8-, 10-, and 12-year pieces. A path counts only if it pays every withdrawal and remains above zero.
Data and important limits
The calculation uses adjusted fund returns plus U.S. government T-bill and inflation data. Personal tax, spreads beyond the stated cost, and investor behavior are not included. A real fund can differ from its index because of fees and tracking.
Keep comparing
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