Number Crunching...

£6.2bn
Osborne's "age of austerity" spending cuts

£23.83bn
Network Rail's "carry on regardless" debt

UPDATE: Network Rail says £23.8bn debt is sustainable.

Eye understands that NR's Board is also confident it can nail jellies to the ceiling.

UPDATE: This from Ithuriel...

Network Rail's debt is sustainable out to 2020, provided:

a) Network Rail can meet its efficiency targets over the rest of Control Period 4

and

b) Network Rail continues to cut maintenance and operating costs year-on-year in Control Period 5 at the same rate as required in Control Period 4

and

c) The Government is happy for Network Rail's funding requirement to remain at the current £5.3 billion a year throughout Control Period 5.

Readers may note that these requirements are not quite all or nothing.

If there are no enhancements in the High Level Output Specification for Control Period 5 then a combination of a) and b), will allow the number in c) to be reduced.

UPDATE: This from Winnie the Pooh...

Despite being a bear of very limited brains even I can see that none of the above provisos are likely to be met.

Which means that NR's level of debt remains at a completely unsustainable level.

Bump, bump, bump...