Alice in Wonderland estimates

I cannot help but love some of the fantasy that goes into the Budget book each year.
This year’s is a case in point. In case you hadn’t heard so concerned is the government to protect its tax revenues it’s going to make finance directors personally sign-off on their company’s tax calculations. OK, that’s understood.
But then the Budget book throws a bucket full of mirkiness over the issue by claiming that the step will save the exchequer £90m over the next couple of years. What? How in all that’s holy did they work that out?
It doesn’t end there. The Budget says naming and shaming tax offenders will save £80m. Right, and my name is the Mad Hatter.
I would love to know the basis for such calculations. Perhaps they come from the Terry Pratchett book of tax. If you have any ideas, let me know.

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