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Rate comparison

Why can a 0.1% difference become large?

Why small daily return differences can create large gaps over time.

A daily difference between 1.0% and 1.1% looks small at first. Repeated through compounding, that difference also compounds and can widen quickly.

3 min read

Small differences repeated many times

A 0.1 percentage point difference may look negligible over one day.

In compounding, each day starts from a changed amount. The difference creates a larger base, and that larger base creates a larger next difference.

Change one condition at a time

If you change principal, duration, and return together, it becomes hard to know what caused the final difference.

ReturnLab fixes the principal and duration, then compares return scenarios side by side so the rate effect is easier to read.

Real markets are not constant

The calculator assumes the same rate repeats every day. Actual investing includes losing days, costs, taxes, slippage, and execution risk.

Use the output as a sensitivity check, not as a promise of future performance.