> Anything less than 40 and you could more economically pay someone to calculate directly. Hiring someone to do the math would defeat the point. The idea was t

> Anything less than 40 and you could more economically pay someone to calculate directly. Hiring someone to do the math would defeat the point. The idea was to eliminate human error when doing something like printing tables of common functions like sines or cosines. A lot of effort went into designing a printer, as they couldn't have humans recording the results without re-introducing human error.