Safe haven
An asset investors buy when they are worried, because they expect it to hold its value: usually US Treasuries, German Bunds, gold, the US dollar, the Swiss franc and sometimes the yen. Heavy buying pushes bond prices up and yields down.
Example
On 22 October 2026 the US 10-year yield had its biggest one-day fall in more than two years as investors fled a tech sell-off.
Explained in