Yet another woman with a successful corporate job is leaving to follow her ludicrous middle-class passion.

Francesca Johnson, 38, no longer feels fulfilled by an upper-management role with a steady income and instead plans to stake her future on a niche, painfully bourgeois business idea.

Johnson said: “This will be my last month at Barclays as head of systems strategy. Instead, I’m going to use recycled textiles to make eco-friendly clothing for cold water swimming.

“The idea came to me at Hampstead Heath Ponds when I saw all these other posh ladies doing lengths. I realised then there was money to be wrung out of them and I cared deeply about the environment and those things.

“My first collection will be out next spring, with prices starting at £499 for a bespoke wetsuit. No one’s thought of this particular idea before, so there’s clearly a demand.

“My friends have been really supportive. Tilly quit her job in publishing to start growing heritage leeks and Zara packed in management consultancy to build book-themed gingerbread houses. I must ask how those businesses are doing.

“Luckily I can do this because my husband Hugh is a hedge fund manager. I explained that when the company’s gone global, I’ll hire him as CFO on even more money, but strangely he just sighed and looked sad.”