Every investment calculator asks the same question:
"What annual return rate should I use?"
Pick 12% and your projection is fantasy.
Pick 5% and you will give up before you start.
Here is the real number — and why it matters more than you think.
The number you should use: 7%
The S&P 500 has returned approximately 10.0% per year on average since 1928. That is the headline number you will see everywhere.
It is also slightly misleading. After adjusting for inflation (which averages around 3%), the real return is closer to 7%. For long-term planning, 7% is the number professionals actually use.
Why 7% and not 10%?
Because in 30 years, $1,000,000 will not have the same purchasing power as today. Inflation eats roughly 3% of your money per year. To plan in today's dollars — meaning, what your future money will actually feel like — you subtract inflation from the nominal return.
If a financial product promises "12% returns," it is either lying, ignoring inflation, ignoring fees, or assuming you got extremely lucky. The S&P 500's long-term real return has been roughly 7% — and that is one of the best long-running asset classes in human history.
What about active funds and stock pickers?
Most beginners assume professional fund managers can beat the market. They cannot. 80-90% of active funds underperform the S&P 500 over 20 years — after their fees are deducted. The remaining 10-20% are mostly luck. You cannot identify them in advance.
This is documented in decades of academic research (the SPIVA reports, if you want sources). The conclusion: do not try to beat the market. Be the market.
What rate to use for which goal?
- Long-term retirement projections (30+ years): 7% real return. Honest, conservative, plannable.
- Short-term aggressive forecasting (5-10 years): 5-6%. Markets are volatile in the short term.
- Showing the upside to motivate yourself: 10% nominal. The headline number, accurate but not inflation-adjusted.
- Bonds and high-yield savings: 3-5%. Different asset class, different math.
What this changes about your plan
$200/month for 35 years at 10% becomes about $760K. At 7%, it becomes about $360K. Big difference. And the second number is closer to what you will actually feel.
Plug in your real timeline and a 7% return rate to see what your money will buy in today's dollars. The number will be smaller — and far more useful for planning.
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