$2,500 a month starts at 6% a year.
Can a prefunded cash pot make QQQ safer to retire on?
Strategy in short: Start with 12 months of spending in T-bills. Each month, sell up to 0.5% of the opening portfolio to refill the pot, capped at another 12 months of current spending.
Retirement answer: QQQ with a prefunded cash pot supported more starting spending than Always QQQ: 2.2% versus 2.1% a year funded 30 years in at least 95% of both sets of histories. These are historical thresholds, not recommended spending.
Return comparison: Both QQQ with a prefunded cash pot and Always QQQ ran out of money while paying this demanding withdrawal example.
$500,000 with $2,500 monthly withdrawals
Both paths paid the same inflation-adjusted spending. The chart shows how the rule changed the money left behind.
See when the pot prevented forced QQQ sales
The pot pays withdrawals first. Scheduled QQQ sales refill it gradually, so a retirement does not have to sell the full monthly amount during every market fall.
The strategy held between 0% and 100% in the risky asset while paying the same monthly withdrawals.
During the lower-exposure months, QQQ rose in 140 months and fell in 95 months. That is where the rule either gave up gains or avoided losses.
QQQ with a prefunded cash pot$0-100.0% deepest fall
Always QQQ$0-100.0% deepest fall
April 1999 through June 2026. Distributions are reinvested. The calculation charges 0.10% of each risky asset bought or sold. Monthly spending starts at $2,500 and rises with inflation. Past results do not predict future results.
Did the spending pot make monthly withdrawals safer?
By March 2010, Always QQQ had run out while QQQ with a prefunded cash pot still had $26,650.
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.
One year of the same spending exceeded everything left in the portfolio.
The portfolio had run out of money.
What funded at least 95% of both history tests?
QQQ with a prefunded cash pot supported a 2.2% starting annual withdrawal for 30 years: 325 ordered starts and 4,769 of 5,000 mixed histories funded every withdrawal.
These are historical thresholds, not recommended spending amounts or a promise of future success.
Test if QQQ with a prefunded cash pot 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
- QQQ with a prefunded cash pot
- 249 funded
- Always QQQ
- 247 funded
5,000 histories built from 8–12-year pieces
- QQQ with a prefunded cash pot
- 3,870 funded
- Always QQQ
- 3,856 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
Start with 12 months of spending in T-bills. Each month, sell up to 0.5% of the opening portfolio to refill the pot, capped at another 12 months of current spending.
A cash buffer changes the timing of sales, not the underlying return of QQQ. Its value depends on whether avoiding depressed-price sales outweighs the growth given up in T-bills.
Can I trust these results?
My evidence-weighted estimate is about 60% that the main effect would persist in a new long market period. That makes the result plausible, 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
See where this strategy ranks.
Use this result
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Enter what you have and what you want to spend each month. Compare three portfolios against the same market history. Your financial figures stay in your browser.
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