Keep the reference and attempt separate
The CSV has columns for variables, required conditions, units and a boundary check, followed by the independent attempt, correction and next recall date. Replace the NPV demonstration row with the formula you are revising.
Choose a check that reveals a common error
For NPV, a zero discount rate leaves an ordinary sum of signed cash flows. For a probability, bounds of zero and one help detect an invalid result. The check should relate to the formula’s domain rather than be a generic tick box.
Use the correction as the next prompt
If the missing condition was the period convention, test that condition on the next attempt. The worksheet supports a repeatable study routine; its dates are your chosen schedule rather than a guaranteed optimal spacing rule.