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FOS-RCH HP-35 Economics and Statistics Programs

The HP-35 wasn't programmable, but the users of this mighty device really wanted to write some programs for it. Mainframe time was deucedly expensive, though, and the mainframes couldn't keep up anyway, at least not in the mathematical calculating arena.

Dr. Fred O. Simons and Dr. Richard C. Harden of Orlando, Florida, were not deterred. They were happy to write programs for the HP-35. They just had to be a little clever as to formatting and storage. They came upon the idea of defining algorithms as step-by-step instructions that would be written on business-card-sized cards so the customer could stick them into the case with the calculator.

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