The monthly amount feels small. The years don’t.
Whether it’s an adult child you keep housing, a car payment past your means, credit-card debt that never clears, a relationship that draws on you, or any habit that bleeds cash every month — the money behaves identically. This shows the part you can’t see: not the cash itself, but the wealth that cash would have become if you invested it instead — and how each time it comes back, the cost stacks higher.
Runs on your device. No account, nothing saved, nothing sent.The drain
What it costs you each month it’s active — the cash that actually leaves your pocket, whatever the source.
Your horizon
Every dollar is measured forward to here — that’s why money that left years ago still costs you.
Your money
What the same money would have done if invested instead.
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The more the markets grow, the more wealth you give up by tying this money down. Range = the 10th–90th percentile across 2,000 simulations.
The cost that never recovers
The pile of wealth you forgo. It steps up with each stretch and keeps compounding in the quiet years between — the gap to the cash you spent only ever widens.
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The model
A Monte Carlo simulation runs 2,000 possible market futures. In each one, every dollar that leaves you during an active stretch is instead invested, and grown forward to your horizon at a randomly drawn return path.
Why short stretches still cost a lot
A dollar that left early is missing — with all its compounding — right up to your horizon, long after the drain itself ended. Each time it comes back it adds a fresh set of withdrawals, so the losses stack instead of resetting.
What goes in
- Monthly returns drawn from a log-normal distribution:
exp((μ − ½σ²)/12 + σ·Z√(1/12)) − 1 - Contributions switch on only during active months — the real on/off pattern, not a smooth stream.
- Emergency cash is held the whole horizon (you never stand it down while it keeps recurring); its drag is the market growth it misses versus the small yield it earns.
- “Typical” is the median outcome; the range is the 10th–90th percentile across all simulations.
What it is not
It makes no judgment about the source — an adult child, a car, a card, a relationship, a habit. It only counts money that actually leaves your pocket. It is an estimate, not a prediction — markets, costs, and timing will differ.
This is not financial advice. POSTADS does not offer financial, legal, or tax advice. This tool is a private estimate to help you see one side of a decision — the financial side. Only you can weigh it against everything a number can’t measure.