Revenue wants to exclude capital (8)
I believe the answer is:
earnings
'revenue' is the definition.
(I've seen this before)
'wants to exclude capital' is the wordplay.
'wants' becomes 'yearnings' (a yearning feeling is a feeling of want).
'to exclude capital' means to remove the first letter.
'yearnings' with its initial letter taken away is 'EARNINGS'.
(Other definitions for earnings that I've seen before include "Grannie's (anag) -- income" , "Salaries etc" , "Monies obtained in return for labour or services" , "Wages for grannies" , "Revenue" .)