Mary Shaw

Essential reading

Once information is loaded into a spreadsheet, it acquires properties that it may not deserve – a process called reification.
Errors in the data, formulas, or manipulation of spreadsheets could be costly, even devastating.
Spreadsheet audit and review procedures are an essential part of almost all City of London financial transactions.
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.
Research concludes unanimously that spreadsheet errors are both common and non-trivial. We must seek ways to reduce spreadsheet errors.
Every study that has looked for errors has found them in considerable numbers. Spreadsheeting's childhood is over.
Incorrect use of Excel's NPV function is a common source of spreadsheet errors. We show several pitfalls and ways to avoid them.