Educational information, not individual financial advice.
Key Takeaways
Open your forecast page and you'll see a line that climbs (hopefully) from today out to age 95 or so. That line is doing more work than it looks like. This is a quick guide to reading it without overinterpreting any single point.
Each point on the line is your projected net worth in that month — assets minus liabilities, summed across everything Horizons knows about your situation. The number compounds: investment returns grow your assets each month, debt interest eats into them, contributions go in, expenses go out. By month 240 (twenty years out), the line reflects 240 monthly compounding steps, each one tiny but additive.
Read the trajectory, not the point. The forecast is a model. The model is wrong about specifics — exactly when you'll get a raise, exactly what 2031's market will do, exactly how your kid's college will pan out. The model is useful about shape: is the line going up or down? Does retirement still work? Where does my net worth peak?
A healthy forecast bends visibly at every life event. If your line is straight, something's missing.
If you can't see your retirement age on the chart, your forecast isn't modeling it. Check your income end dates and your retirement Plan of Record entry.
Below or behind the forecast line, you'll often see a cone — a fan-shaped band of color that widens with time. That's the Monte Carlo result: 2,000 simulated futures, each with different market returns, each plotted on the same axes.
The center of the cone is roughly where the deterministic line sits. The edges show the 10th–90th percentile range. Read the width of the cone, not the height of the line. A narrow cone means the outcome is mostly insensitive to market returns; a wide cone means luck dominates.
If your retirement readiness depends on the line being above $X, but the 10th percentile of the cone is below $X, you have a real risk — even though the central forecast looks fine.
Every input on Horizons feeds the forecast. The biggest levers, ranked roughly by impact for most people:
Use the What-If panel on the forecast page to see how each lever affects the line in real time. Sliding inflation from 2.8% to 3.5% can shift the line by hundreds of thousands of dollars over a 40-year horizon.
If any of these answers surprise you, your inputs may have a gap. Click a milestone marker for the underlying entity and edit from there.
How should you interpret the exact dollar value your forecast shows for, say, 18 years out?
Try it in your scenario
Known limitations
Sources
Educational information distilled from the Horizons engine methodology — not individual financial advice.
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