At the pinnacle of his power Samuel Insull sat on the directorates of 85 companies, was chairman of 65, president of 11, and through his holding companies controlled more than 6,000 power units, employing 72,000 workers in 324 steam, 196 hydro-electric generating plants, 89 gas plants, 328 ice plants. His companies served 1,700,000 customers, a population of 10,000,000. There were 600,000 security holders. The valuation of the system rose above the 3,000,000,000 dollar mark.
