These predictions proved incorrect and as the cable television industry boomed in the mid- to late 1970s, Scientific-Atlanta grew with it. The company's profits ballooned by 40 percent a year from 1972 on as Scientific-Atlanta came to dominate the market it had largely pioneered. In 1976, as sales rose to more than $45 million, the company greatly expanded its manufacturing, laboratory, and office space at its headquarters. It sold two-thirds of the 3,000 satellite earth stations purchased by cable companies during the 1970s, enabling its clients—broadcasters such as Home Box Office (HBO) and Showtime/The Movie Channel—to become pillars of the cable broadcasting industry. Scientific-Atlanta's strength in satellite earth stations helped to enhance its overall sales of cable television equipment, and the company also began to market other components necessary to operate a cable television system.