The Global Copper Miners ETF ($COPX) just hit 11 straight weeks of losses—the longest losing streak since it launched in 2010. That breaks the old record of 10 weeks back in 2015.

Over this stretch, $COPX is down 24.7% and sitting near its lowest point since mid-December. What's wild: it was up 34.8% in August. Now it's barely flat for the year, down 0.4%.

Copper futures aren't helping either—down 6.7% over the past month to $6.28 per pound, the weakest since July.

This is a sharp reversal for a sector that looked strong just a few months ago. Copper is often seen as a gauge for global economic health, so this pullback raises questions about demand, China's recovery, and whether industrial activity is cooling faster than expected.

If you're watching materials or industrials, this is worth paying attention to.