xkcd #3232: Countdown Standard
Title text:
Anyone who is caught counting 'three ... two ... one ... zero ... GO!' will be punished with a lifetime of eating only ISO standard food samples.
Transcript:
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Source: https://xkcd.com/3232/
I find Thursday (for this week) and Thursday next (for next week) adequate and am seldom called on for clarification, seems to follow the pattern of the rule (thanks for that) but is more economical.