This article is from the Kool-Aid FAQ, by Paul and Bess Dawson-Schmidt email@example.com with numerous contributions by others.
The first four NUMBERS in the code indicate the date. The first
indicates the year (ie. 4 for 1994, 0 for 1990 etc). The next three
numbers are the day of the year it was produced (ie. 001 for Jan 1 up to
365 for Dec 31). The letter indicates place of production. In the US,
Chicago is represented by A, EV is for Evanston, Illinois, and M for
Modesto, California. In Canada CO stands for Cobourg Ontario.
-Ron Gregory & Bernard Marrocco