The big mac index was cooked up by The Economist 34 years ago as an easily digestible way to access exchange-rate theory.

In other words, it was meant to look at the levels of various currencies or what a Big Mac cost if you paid in dollars, yuan, rupees.

But is the Big Mac index suitable for the age of plant-based burgers, vegan sausage rolls and tofu quinoa bowls?

The Economist recently acknowledged that “fast food has become healthier of late” but insisted that a McDonald’s Big Mac remained “the dish of choice” for economics enthusiasts. And it gave us the numbers: a Big Mac costs 21.50 yuan, or $3.12, in China, compared with $5.67 in America, which suggests that “the yuan is 45% undervalued against the dollar” and the greenback remains strong.

Fine.

At some point, there may be a liverish appetite for burgernomics.