On the big days of this month’s earnings season, The Australian Financial Review’s Chanticleer columnists James Thomson and Anthony Macdonald have extracted the gold from the key profit results.

JT: When a stock plunges like AI technology group Appen did on Monday following its first-half results – down a painful 29 per cent in a day – we’d usually call that a surprise. But that’s not the case when it comes to Appen, which has seen 14 peak-to-trough falls of more than 20 per cent over the past five years, and five in the last 12 months alone.