“During 2011 the materials sector has underperformed,” said Investors Intelligence technical analyst Tarquin Coe, pointing to the decline in Materials Select Sector SPDR.

“A declining trend channel is evident since the start of the year. That road leads back down to the 2010 low of $27.67 [a share],” he said in a newsletter. “That would be the third test of that level and should it fail to provide support a two year head-and-shoulders top would be activated. The bearish pattern has a target back down to the lows of 2009.”

The materials ETF’s top holdings are DuPont (NYSE: DD), Monsant (NYSE: MON) and Freeport McMoRan (NYSE: FCX).