How to Read the Two Charts

Turn colored lines into decisions you can explain to a friend

Two charts appear when you run a projection, and they answer different questions. The first shows where your balance goes over time. The second shows who did the work — you or the market. Reading both properly changes how you interpret the result.

Chart one: the balance curve

This line plots your projected balance year by year. The important thing about it is the shape, not the endpoint.

For the first several years it looks nearly straight, because your deposits are large relative to the balance. Later it bends upward, because growth on a bigger base starts to outrun the deposits.

That bend is the whole argument for staying invested. If you exit during the straight part, you never reach the part that curves.

Hover across the line and check a few specific years rather than only the end. Year 5, year 15, and year 25 tell you whether the plan is on pace at the points where you are most likely to get discouraged and quit.

Chart two: contributions versus growth

This one splits the ending balance into money you deposited and money that growth created. It is the more useful chart for motivation.

Early on, the contributions block dwarfs the growth block. Around the middle of a long horizon they cross over. By the end, growth is often the larger share.

Find roughly where the crossover happens in your scenario. That year is when your portfolio starts contributing more than you do.

Key takeaway The balance chart shows you the path. The contributions-versus-growth chart shows you when your money starts pulling its own weight. The second one is the reason to be patient during the first.

Key points

A straight-looking early curve is normal, not a sign the plan is broken.
The crossover year is when growth exceeds your total deposits.
Shorter horizons may never reach the crossover — that is expected.
Raising the return pulls the crossover earlier; lowering it pushes the crossover later.

What the charts deliberately leave out

Neither chart shows volatility. The balance line rises every single year because the model applies the same return annually, while a real account has years where the line drops and stays down for a while.

Neither chart shows inflation either. A balance of $900,000 in thirty years is drawn in future dollars, and those dollars buy less than today's. If that matters for your goal, run an inflation check separately and compare.

Finally, the charts assume you never withdraw. Real accounts get raided for emergencies, down payments, and tuition. Knowing these three omissions keeps you from treating a smooth projection as a forecast.

Use the charts to compare, not to predict

The strongest way to use these charts is to run two scenarios and compare the shapes, rather than fixating on one ending dollar amount.

Change one input, rerun, and watch which part of the curve moved. Contribution changes lift the whole line evenly. Return changes bend the tail. Time changes extend the bend.

Once you can predict which way the line will move before you click, you understand your own plan well enough to explain it to someone else.

                    Do not over-read the endpoint: the final dollar figure carries a decades-long assumption. The shape of the curve is the durable lesson; the last digit is noise.
                

Try these inputs

Long horizon: $2,000 start, $250/mo, 8%, 35 years — find the crossover
Short horizon: $2,000 start, $250/mo, 8%, 10 years — see why it never crosses
Same 35 years at 5% — watch the crossover move later

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