Lira and Y2K in one place
COBOL on PDP-10 systems allowed for 10 digit numbers - you could choose where the decimal point lay. In the system that I worked on, we had S9(6)V9(4) fields for unit prices, but if the country code indicated Italy, we had to use S9(6)V99 instead.
Dates on this system were held in 4-digit YYMM format - my first task as a fresh-faced programmer (in late 1978) was to change all the code (and the data) that regarded 7912 as an indicator for (e.g) cancelled orders - we couldn't take any more room, so just used 9912 as the new indicator. The system presumably died before Y2K, I'd moved on a couple of times by that point.