Supermarkets are nothing short of a modern miracle. A large Tesco Superstore carries around 40,000 product lines, sourced from over 20,000 British farmers and 70 countries, available year-round. A feat of logistics unimaginable just a few generations ago. Yet in Britain today the supermarket is cast not as a marvel but as a villain, blamed for the very prices it has spent a century driving down. A strong majority, 70 per cent, believe that supermarkets are making excessive profits. However, this conclusion has largely been driven by misinformation. The public believes that supermarkets are making 32 pence for every £1 that shoppers spend. In reality, their margins are around just 3 pence per £1 spent, compared with the all-industry net margin benchmark of roughly 8.5 pence. When you inform voters about the profits supermarkets make, public opinion shifts dramatically. The level of agreement that supermarkets are profiteering drops to 32 per cent, while disagreement rises to 44 per cent. That represents a fall from +58 to -12 in net agreement that supermarkets are profiteering, an unusually large shift in public opinion from providing just a single piece of additional information. My latest for @iealondon: economicaffairs.co.uk/p/the-…