Thanks, I really appreciate you made the effort to find some actual stats, but with respect, that doc is from march 2012. I don't know if the data is still relevant now (though it may be).
We need some solid stats by an independent party which is why I'm happy one is going to be looking into it.
FYI from that document, let me quote cos it's interesting: cost estimates in march 2012:
2.9 Route package cost summaries
2.9.1 The phase one total cost estimate is £16.3 billion within a cost range of £15.4 billion to £17.3 billion. [...]
2.9.2 The phase two total cost estimate is £17.1 billion within a cost range of £15.7 billion to £18.7 billion. [...]
2.9.3 The full Y network cost estimate is £33.4 billion within a cost range of £30.9 billion to £36.0 billion. [...]