1860 – Born on the 29th of February.
1875 – Hollerith entered the City College of New York.
1879 – Graduated from the Columbia University School of Mines with an "Engineer of Mines" degree.
1880 – He listed himself as a mining engineer while living in Manhattan.
1890 – He completed his Ph.D. at Columbia University.
– On the 15th of September, he married Lucia Beverley Talcott.
– He built machines under contract for the US Census Bureau, which used them to tabulate the census in 2.5 years.
1896 – He started his own business when he founded the Tabulating Machine Company.
1929 – Died on the 17th of November of a heart attack and was buried in the Oak Hill Cemetery in Georgetown, Washington, D.C.