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The spreadsheet range that left countries out

In 2010, a famous economics paper argued that when a country's public debt passes 90% of GDP, economic growth drops sharply, a finding cited by politicians around the world to justify austerity budgets. Three years later, when a graduate student obtained the authors' original working spreadsheet, he discovered that a spreadsheet range had accidentally left five countries out of one calculation. Their critique also identified other data and methodological choices; the coding error alone was not the whole dispute.

5–7 min

Questions you could explore

  • How can an innocent-looking range change a result?
  • Which disagreements remain after a spreadsheet error is fixed?

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