Treasury Minister Alex Allinson says he doesn't know how much a 2 per cent rise in income tax, ringfenced for healthcare, has raised.
He faced a question for written reply from Douglas North MHK John Wannenburgh about the rise imposed last year.
Dr Allinson said Treasury had estimated the rise would generate around £20 million of extra income tax.
But he said until all last year's tax returns had been submitted, it wasn't possible to give an exact figure.
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