America may soon be in recession, according to a famous rule

For financial markets the Holy Grail is a perfect leading indicator—a gauge that is both simple to monitor and consistently accurate in foretelling the future. In reality, such predictive perfection is unattainable. It is often hard enough to grasp what is happening in the present, let alone the future. A perfect real-time indicator would thus be a potent goblet of knowledge, if not quite the Holy Grail, for investors and analysts to drink from. Recently they have turned their attention towards one impressive candidate: the Sahm rule.Developed by Claudia Sahm, a former economist at the Federal Reserve, in 2019, the rule would have been capable of identifying every recession since 1960 in its early stages, with no false positives. This is no mean feat given that the body which officially declares whether the American economy is in recession sometimes needs a full year of data. The Sahm rule, by contrast, typically needs just a few months.