[CQ-Contest] CQWWDX CW

[Rich K2WR]

Thanksgiving is the 4th (not the last) Thursday in November.  (There are five Thursdays in November whenever November 1st falls on a Wednesday or a Thursday.)
CQWW-CW, as everyone here knows, is the last full weekend of November.
Put these two rules together, examine the calendar, and the result is that CQWW occurs before Thanksgiving whenever November 1st falls on a Friday.
There is no regular sequence (or, at least, no simple regular sequence) due to leap years.  Century years also disrupt the sequence, but there has only been one of those since amateur radio began (2000) and that was a leap year.  Within any 14 year period, CQWW should precede Thanksgiving twice.

Rich K2WR