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1890
Tabulating the US Census
Herman Hollerith (1860–1929)

Herman Hollerith (February 29, 1860 – November 17, 1929) was an American businessman, inventor, and statistician who developed an electromechanical tabulating machine for punched cards to assist in summarizing information and, later, in accounting. His invention of the punched card tabulating machine, patented in 1884, marks the beginning of the era of semiautomatic data processing systems, and his concept dominated that landscape for nearly a century.[1][2]
Hollerith founded a company that was amalgamated in 1911 with several other companies to form the Computing-Tabulating-Recording Company. In 1924, the company was renamed “International Business Machines” (IBM) and became one of the largest and most successful companies of the 20th century. Hollerith is regarded as one of the seminal figures in the development of data processing.[3]
“When the US Constitution was ratified, it mandated that the government conduct an “actual enumeration” of every free person in the union every 10 years. As the number of people in the nation grew, the enumeration took longer and longer to complete. The 1880 Census counted 50,189,209 people. It took 31,382 people to perform the count and eight years to tabulate the results, producing 21,458 pages of published reports. So, in 1888, the Census Bureau held a competition to find a better way to process and tabulate the data.
American inventor Herman Hollerith had worked briefly at the Census Bureau prior to the 1880 census and in 1882 joined the faculty of MIT, where he taught mechanical engineering and experimented with mechanical tabulation systems. His early systems used long rolls of paper tape with data represented as punched holes. Then, on a railroad trip to the American West, Hollerith saw how conductors made holes on paper tickets corresponding to a person’s hair color, eye color, and so on, so that tickets couldn’t be reused by other passengers. Hollerith immediately switched his systems to use paper cards.”

“Hollerith entered the 1888 competition and won, his system being dramatically faster than those of the two other entrants. On January 8, 1889, he was awarded a US patent on “method, system and apparatus for compiling statistics,” originally filed September 23, 1884.”

“Hollerith’s system consisted of a slightly curved card measuring 3.25 by 7.375 inches (83 millimeters by 187 millimeters). A human operator punched holes in the card with a device called a Pantographic Card Punch, with holes in specific locations to signify a person’s gender, marital status, race, ownership and indebtedness of farms and homes, and other information. For tabulation, the cards were passed through a reader with micro switches to detect the presence of holes and electromechanical circuits to perform the actual tabulation.”
SEE ALSO The Jacquard Loom (1801), ENIAC (1943)
A woman with a Hollerith Pantographic Card Punch, which creates holes in specific locations to signify a persons gender, marital status, and other information. This photo is from the 1940 US census.”