Paul B. Cragg

Essential reading

Only a quarter of survey participants were satisfied with their spreadsheet testing. Their techniques are largely manual and lack formalism.
Your spreadsheets may be disasters in the making. Strive for spreadsheets that are validated, reliable, and auditable.
Spreadsheets have errors like dogs have fleas. Nine out of every ten spreadsheets suffer some error, and consequences can be severe.
We are conscious of very few of our errors. When people are confronted with their actual error rates, they are typically shocked.
Incorrect use of Excel's NPV function is a common source of spreadsheet errors. We show several pitfalls and ways to avoid them.
See our bibliography of spreadsheet best practice, risk management, errors and testing, and methods for improving spreadsheets.
"Oh My God" my formulas are not working! This article covers most of the reasons for Excel formulas not working. And how to fix them.
Creating a slow spreadsheet is easy. Creating an efficient spreadsheet requires more thought and application of specific techniques.