Portugal's structural hole is just over 3% of GDP - half the size of America's.

BBC: Why is America's fiscal cliff more worrying than Europe's?

Because it means, even on the most optimistic assumptions, the OBR is going to tell the chancellor that the structural hole he set out to fix is actually larger, now, than when he took office.

BBC: Digging to stand still

If the FT's economics editor, Chris Giles, is right, the OBR is also likely to tell him (again) that the structural hole in the public finances is larger than previously thought, meaning even more austerity is required, well into the next parliament.

BBC: George Osborne chooses his words carefully

Our potential growth rate will be even slower, unemployment will be higher, and the structural hole in the public finances will be even larger, requiring the government to impose even greater tax rises and spending cuts to bring the national debt onto a downward path.

BBC: Inflation: Balancing the risks

That is a larger structural budget hole than any of the troubled eurozone economies, including Portugal and Greece.

BBC: Why is America's fiscal cliff more worrying than Europe's?