> The so-called yield curve is perilously close to predicting a recession — something it has done before with surprising accuracy — and it’s become a big topic on Wall Street.

> The yield curve is basically the difference between interest rates on short-term United States government bonds, say, two-year Treasury notes, and long-term government bonds, like 10-year Treasury notes.

> Typically, when an economy seems in good health, the rate on the longer-term bonds will be higher than short-term ones. The extra interest is to compensate, in part, for the risk that strong economic growth could set off a broad rise in prices, known as inflation. Lately, though, long-term bond yields have been stubbornly slow to rise — which suggests traders are concerned about long-term growth — even as the economy shows plenty of vitality.