不知铜价如何， 有句话 “Copper has a PhD in economics”

"Copper has a PhD in economics" is a popular saying meaning copper's price is a great indicator of global economic health because it's vital for construction, electronics, and infrastructure, so demand (and price) rises with economic growth and falls during downturns, though its predictive power is sometimes debated due to factors like green energy transitions. It's nicknamed "Dr. Copper" for its ability to signal economic shifts, reflecting broad industrial demand.