This question crops up a lot, and there is a way of looking at it
that answers many ancillary questions as well.
The contest requires that you acquire some information, which we
can refer to as "content", to borrow a term from the data processing
field. The fact that some of that content, the power, is expressed
as "100" or "ATT" or even "0R1K" is "encoding", which is a different
concept than "content", again from the data processing perspective.
In other words, the contest sponsor wants to see the power in some
form that they understand, and the ordinary number is (probably) the
preferred form. So when you hear "ATT" or "5NN", log "100" or "599",
respectively. Everyone will allow "K" or "KW" as a convenient
abbreviation for "1000", so you don't accidentally lose a zero while
Short form: CW operating uses a lot of abbreviations to save dits
and dahs, contest log processing values clarity, so translate those
abbreviations to a number (except for "KW", if you want).
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