vocabularies

The count dimension for a length of text — how many characters a text value spans. Region-neutral and universal: a character is a character everywhere, the same count in any locale. A dedicated count dimension in the pool's per-counted-thing practice (as SeatCountUnits counts seats, TierCountUnits counts tiers); it counts characters of text, not physical items (QuantityUnits) or repeated actions (CountUnits).

Answers the question: maximum length.