Welcome, contestants, to Inflation Island, the only reality show where you pay to watch and the prices vote you off your own grocery list. This month’s episode crowned a new champion: motor fuel. Inflation, the rate at which everyday prices climb over a year, rose to 3.7% in the twelve months to September, faster than expected, with petrol doing most of the heavy lifting.

The mechanism is simpler than the set design suggests. When fuel costs more, it does not stay at the pump. Lorries cost more to run, so the lettuce costs more to reach the shop, and the shop passes that on with a shrug. The prices are the stars here, and they are very good at their jobs.

Meanwhile, the people running the set have assured us the show is under control, with midterm elections coming up in November and everyone eager to look like they have a plan. Nobody has yet explained what the audience is supposed to do besides keep watching.

So what does this mean for you? If your savings account pays less than 3.7% a year, your money is quietly shrinking in real terms, which is the reality-show version of being slowly voted off the island. Check the rate this week. Your grocery receipts will not be getting any smaller.