Aren’t you glad there are Excel spreadsheets today?
Before computer spreadsheet programs, people still needed to calculate large amounts of numbers. It would usually be done on a huge chalkboard (or an erasable pen and a huge pane of glass/plexiglass) set up like a giant table or balance sheet. Here’s the caption from this photo from January, 1943.
“Chicago, Illinois. Mrs. Marie Griffith, manager of the information room, at one of the boards listing rates to points all over the country at the Union Station. Photo by Jack Delano, Office of War Information.”
This woman is calculating all the fares for each fare type and location. She’s wearing a jacket over her outfit to protect her clothes from chalk dust. The original photo is in a very high resolution: click on it to see just how much work had to go into making these calculations, even though today they would be very easy to automatically compute.