The automobile industry contributed a great deal to the business boom. Henry Ford, by adapting assembly-line techniques and concentrating on a standardised model, the Model T, brought the car to the masses. By 1925, he was producing a car even ten seconds. There was competition from other manufacturers. By 1929, there we nearly 27 million cars - 1 car for every 5 Americans. In 1929, the car industry employed 450,000 workers - 7% of all manufacturing wage-earners. The automobile industry stimulated other industries - steel, rubber, oil etc