Spreadsheet Errors and Risks: Statistics and Notable Failures

Last updated: June 2026

Spreadsheets sit underneath most of the world's financial decisions. Decades of academic audits and a string of public failures show how often they go wrong, and how much it can cost. Below is what the research and the record actually say, with the primary source for every figure.

How common are spreadsheet errors

94% of audited business spreadsheets contained errors. Across the field audits compiled by Prof. Raymond Panko (University of Hawaii), the weighted-average share of audited operational spreadsheets found to contain errors was 94%. The review spans studies conducted from 1995 onward using sound audit methodology. (Panko, "What We Know About Spreadsheet Errors")

~5% average cell error rate in operational spreadsheets. Panko reports an average cell error rate of roughly 5% across the operational spreadsheets audited. The point that matters: even a low per-cell rate compounds, because a real financial model has thousands of formula cells, so the probability that at least one material error exists approaches certainty. (Panko, "What We Know About Spreadsheet Errors")

How much finance still relies on spreadsheets

96% of FP&A professionals use spreadsheets as a planning tool at least weekly. In the 2025 AFP FP&A Benchmarking Survey, 96% reported using spreadsheets for planning at least weekly, and 93% for reporting at least weekly, despite years of investment in dedicated FP&A platforms. (Association for Financial Professionals, 2025 FP&A Benchmarking Survey)

58% of finance leaders still rely on spreadsheets as their primary automation tool. Reported in Rossum's Document Automation Trends 2025, even as AI and dedicated tools become available. (Rossum, Document Automation Trends 2025, as reported by The CFO)

What spreadsheet errors have cost

$6.2bn — JPMorgan's "London Whale" loss, with a spreadsheet flaw among the contributing operational failures (2012). The bank's own management task force found the Value-at-Risk model ran through a chain of spreadsheets requiring manual copy-paste between them, and that one step divided by a sum instead of an average, understating risk. The Excel error was one of several operational flaws behind the loss, not its sole cause. (JPMorgan Chase Management Task Force Report, 2013)

−0.1% became +2.2% — the Reinhart-Rogoff spreadsheet error that undercut a pillar of austerity policy (2010). The influential paper "Growth in a Time of Debt" reported that average growth turns negative (−0.1%) above a 90% debt-to-GDP ratio. Economists Herndon, Ash and Pollin found that a formula not extended across five rows excluded five countries from the average. Corrected, average growth above the threshold was +2.2%, not negative, weakening the empirical case the figure had been used to support. (Herndon, Ash & Pollin, 2013, via The Conversation)

15,841 COVID-19 cases dropped from England's contact tracing because of a spreadsheet row limit (2020). Public Health England pulled testing data into a legacy .XLS file, whose 65,536-row cap silently truncated results once exceeded. Nearly 16,000 positive cases were not passed to contact tracers during the affected window. (The Register, October 2020)

Sources

Raymond Panko, "What We Know About Spreadsheet Errors", University of Hawaii. Link
Association for Financial Professionals, 2025 FP&A Benchmarking Survey. Link
Rossum, Document Automation Trends 2025 (reported by The CFO). Link
JPMorgan Chase, Report of the Management Task Force Regarding 2012 CIO Losses (2013). Link
Herndon, Ash & Pollin (2013), on the Reinhart-Rogoff error (via The Conversation). Link
The Register, "Excel spreadsheet blunder ... 16,000 COVID-19 cases" (2020). Link

Changelog

2026-06 — Initial version. Seven figures across prevalence, finance reliance, and notable failures. Citigroup ($900M) and the "24% of large businesses" figure were reviewed and excluded (no primary source / not a spreadsheet error).

Spreadsheet Errors and Risks: Statistics and Notable Failures (2026)