NEW YORK (AP) -- The stock market is slightly lower after a six-day advance as several U.S. companies report disappointing earnings.
Norfolk Southern, Procter & Gamble and Avery Dennison fell after reporting their latest quarterly results.
Intuitive Surgical dropped 9 percent after the company said it sold only half has many surgical robots in the last quarter as it did in the same period a year ago.
Not all the earnings news was bad. Delta Air Lines rose 5 percent after its first-quarter earnings climbed.
The Standard & Poor's 500 index fell two points, or 0.1 percent, to 1,877 in midday trading Wednesday.
The Dow Jones industrial average lost 20 points, or 0.1 percent, to 16,494. The Nasdaq composite fell 20 points, or 0.5 percent, to 4,141.