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"Us system programming types used binary. Years up to 65,535 in two bytes, no problem. Even one byte got you past 2200 with a 1970 epoch."

I once wrote a video rental management system back in the early 80s and I couldn't afford a whole byte for the year, let alone two! Even then, I knew the system would not be in use in 10 years time (it wasn't!) so used 4 bits each for month and year, 5 bits for the day and the remaining three bits for rental status. Film titles were stored using a limited uppercase, numbers + some symbols character set using 6 bits per character and a couple of functions to convert a data string into the simple compression format. Storage was a pair of 180KB floppies and only 48K RAM to play with (or whatever was left after LDOS loaded on a TRS-80.)