Every time I see “Kenneth Rogoff, a professor of economics at Harvard University” quoted somewhere:

«Thomas called his girlfriend over to check his eyes weren’t deceiving him.

But no, he was correct – he’d spotted a basic error in the spreadsheet. The Harvard professors had accidentally only included 15 of the 20 countries under analysis in their key calculation (of average GDP growth in countries with high public debt).

Australia, Austria, Belgium, Canada and Denmark were missing.

Oops.

https://www.bbc.com/news/magazine-22223190

I’m sure that guy triple-checks his spreadsheets now, but still….