Tax making wonderful profits (7,5)

I believe the answer is:

capital gains

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'tax making wonderful profits' is the definition.
I can't tell whether this defines the answer.

'wonderful profits' is the wordplay.
'wonderful' becomes 'capital'.
'profits' becomes 'gains' ('gain' can be a synonym of 'profit').
'capital'+'gains'='CAPITAL GAINS'

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(Other definitions for capital gains that I've seen before include "target of 17, 8 [CHANCELLORS STATEMENT] - with 6a" , "Profits from investment sales" , "Profits from the sale of assets" , "post-war Honolulu and Juneau for US?" , "Profit" .)

I've seen this clue in The Daily Express.

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