Passage: Dhahran has the headquarters of Saudi Aramco. The company is the largest oil company in the world with the largest oil reserves in the world, and it produces about 10 million barrels of oil per day. Most of the oil is exported, since local Saudi needs require about 12% of the total production. (See: Saudi Aramco)Eighty-seven years on, Dhahran is still Saudi Aramco's worldwide headquarters and the center of the company's finance, exploration, engineering, drilling services, medical services, materials supply and other company organisations.

Question: How long has Dhahran been the worldwide headquarters of Saudi Aramco?
Eighty-seven years