Reading sensationalist newspaper headlines last week on the credit rating downgrade of Barclays Bank by one of the main agencies, observers could be forgiven for thinking it was a catastrophic event that heralded one of the UK’s biggest lenders’ inevitable collapse. “Barclays rocked by rating downgrade” was a typical example.

Journalists, however, are not alone in their propensity to overreact. Investors, arguably, have the same trait.