During the 25 years that followed the American Civil War, railway track mileage in the United States more than doubled, changing the face of America forever. Rail transportation meant that products made in the East could be shipped West for far less than previously. This allowed for an economy of scale - larger, more efficient factories. The agricultural heartland of America was no longer confined to a market of single day's trip by wagon. Railroad and railroad construction became one of the largest industries during that era. By 1881 one out of 32 people in the United States was either employed by a railroad or engaged in railroad construction.