U.S. stocks were set to open sharply lower on Tuesday as poor forecasts from retailers (including Target Corp and Kohls Corp) for the holiday quarter fed into a market driven lower this week by concerns about demand for iPhones.

Another drop in Apple Inc APPL.O in premarket trading was adding to the pressure as the stock that led the market through much of its bull run looked poised to open at its lowest level since May, putting the tech-heavy Nasdaq on course to fall more than 2 percent at the open.

Should Apple’s loss hold through the day, its shares would have lost more than 20 percent of their value, or around $250 billion, since closing at a record high on Oct. 3.

Retailers also took a hammering with Target (TGT.N) down 11.1 percent after it posted a lower-than-expected third-quarter profit, with some analysts also pointing to evidence of weak demand for consumer electronics in Best Buy’s results.

Read more in Reuters.