Will you actually hit your savings goal?
Some months you save more, some less; returns bounce around. A single "if I save $700 a month…" line ignores all of that. This template projects your balance over three years with the wobble built in, and shows your real odds of reaching the goal.
Personal Finance Intermediate Monte Carlo Pro engine
After you install, this is the model to open.
Will You Hit Your Savings Goal?
- In your spreadsheet, click the Sortia icon in the strip of icons down the right-hand edge. No strip? Click the arrow at the bottom-right to open it. You can also use Extensions, then Sortia, then Open Sortia.
- Click Start from a template and put that name in the search box.
- Pick the card with that name and click Load this template. It arrives on a new tab with real numbers already in it.
This one runs on a Pro engine, and every free install includes five full-quality runs on your own numbers, shared across all five Pro engines rather than five for each. After that, Pro is $199/year.
The answer
Where you land after 36 months, across thousands of scenarios:
- P5 (unlucky)
- $37.2K
- Median
- $45.5K
- P95 (lucky)
- $54.1K
- Reach $40K goal
- 85%
You reach the $40,000 goal about 85% of the time, but roughly 1 in 7 paths fall short, some as low as $37K. That tail is the whole point: it tells you whether to nudge the monthly number up now or accept the risk. Change the goal, starting balance, and ranges to fit your own plan.
The model
A monthly projection: your balance compounds at the return rate and grows by each monthly contribution. Contribution and annual return are both uncertain.
| Current savings | $15,000 |
| Monthly contribution | $400 – $700 – $1,000 (uncertain) |
| Annual return | 2% – 6% – 10% (uncertain) |
| Goal | $40,000 |
| Balance in 3 years | simulated |
Once it is in your sheet
- The model arrives with real numbers in it and runs as it stands, so you can press the button first and understand it second.
- Change the numbers to yours. The sheet marks which cells are inputs and which hold formulas, and most labels carry a note explaining the row.
- Press the run button at the bottom of the panel. It is labeled for the tool you are in, and the result lands on its own tab, with a written reading of it beside the figures.
Never used Google Sheets? Start here goes the whole way, in seven steps, and assumes nothing.
Next question
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- Can you really afford six months off?Can I Afford a Sabbatical?
- What does skipping the salary negotiation really cost you?What Does Not Negotiating the Salary Cost Over a Career?
Every model like this one, and the method behind them: Monte Carlo simulation.