← What a Time Standard Means · Lesson 3 of 4
Percent, not percentile
Club websites use “the B percentage” for different things: a time as a share of a fast time, a claim like “top 30%”, or a time a fixed percent slower than a base. Only the last is how this table is built — the B cut is about 47% slower than the base.
None of the letters says what share of children swim that fast. A percentile would need a count of swimmers, and even then it would count only the swimmers who have a recorded time. The children who never entered a meet are not in that number.
A club page says a B time means “the top 30%”. What is a B cut actually built from?
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