Final answer:
Technology is the main explanation for the growth of the U.S. economy over the last 100 years.
Step-by-step explanation:
One explanation for the growth in the U.S. economy over the last 100 years is technology. Technology is typically the most important contributor to U.S. economic growth. Growth in human capital and physical capital often explains only half or less than half of the economic growth that occurs. New ways of doing things are tremendously important. For example, the United States experienced significant growth in the twentieth century due to phenomenal changes in infrastructure, equipment, and technological improvements in physical capital and human capital. The population more than tripled in the twentieth century, and the human capital of modern workers is far higher today because the education and skills of workers have risen dramatically.