Three weeks I wrote a blog post about how economists define a recession. I pretty quickly brushed aside the “two consecutive quarters of declining GDP,” since this is not the definition that NBER uses. But since that post (and thanks to a similar blog post from the White House the day after mine), there has been an ongoing debate among economists on social media about how we define recessions. And some economists and others in the media have insisted that the “two quarters” rule is a useful rule of thumb that is often used in textbooks.
It is absolutely true that you can find this “two quarters” rule mentioned in some economics textbooks. Occasionally, it is even part of the definition of a recession. But to try and move this debate forward, I collected as many examples as I could find from recent introductory economics textbooks. I tried to stick with the most recent editions to see what current thinking on the topic is among textbook authors, though I will also say a little bit about a few older editions after showing the results of my search.
Undoubtedly, I have missed a few principles textbooks (there are a lot of them!) so if you have a recent edition that I didn’t include, please share it and I’ll update the post accordingly. I also tried to stick with textbooks published in the last decade, though I made an exception for Samuelson and Nordhaus (2010) since Samuelson is so important to the history of principles textbooks (and his definition has changed, which I’ll discuss below).
But here’s my data on the 17 recent principles textbooks that I’ve found so far (send me more if you have them!). Thanks to Ninos Malek for gathering many of these textbooks and to my Twitter followers for some pointers too.Continue reading