Collapse in membership fees? I study sources of club expenditure (10)
I believe the answer is:
subsidence
'collapse' is the definition.
(subsidence is a kind of collapse)
'membership fees? i study sources of club expenditure' is the wordplay.
'membership fees?' becomes 'subs' (fees paid to a club or organisation).
'study' becomes 'den' (term for a study or office).
'sources of' says to take the initial letters.
The initial letters of 'club expenditure' is 'ce'.
'subs'+'i'+'den'+'ce'='SUBSIDENCE'
'in' acts as a link.
(Other definitions for subsidence that I've seen before include "caving in" , "Collapse" , "Sinking of land, maybe due to mining" , "earth movement" .)