#estimates due

NEW YORK | Markets sink as tech and retail fall; oil drops 7 percent

NEW YORK  — Stocks are skidding Tuesday as weak results from retailers and mounting losses for big technology companies push the market back into the red for the year.

Energy companies are slumping because of a 7 percent plunge in the price of oil. Crude is on track for its biggest loss in three years.

Industrial companies are also dropping as the downward momentum in stocks builds after steep…