Outspoken pub reducing headcount by 90%? (5)

I believe the answer is:

vocal

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'outspoken' is the definition.
(I know that outspoken can be written as vocal)

I don't understand the remainder of the clue.

Can you help me to learn more?

(Other definitions for vocal that I've seen before include "Audible in protest" , "speaking loudly" , "For, giving, voice" , "With lots to say" , "Freely expressing opinions" .)

I've seen this clue in The Guardian.

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