In favour of drink before start of inspection, on balance (10)

I believe the answer is:

proportion

I'm a little stuck... Click here to teach me more about this clue!

'balance' is the definition.
(I've seen this before)

'in favour of drink before start of inspection on' is the wordplay.
'in favour of' becomes 'pro' (I've seen this before).
'drink before' becomes 'port' (I've seen this before. I am not sure about the 'before' bit.**).
'start of' suggests taking the first letters.
The initial letter of 'inspection' is 'i'.
'pro'+'port'+'i'+'on'='PROPORTION'

Can you help me to learn more?

(Other definitions for proportion that I've seen before include "balance" , "Part - one needs a sense of it" .)

I've seen this clue in The Telegraph.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.