Yep, I could have knocked that out for a mere £104 million - a £1 million pound saving to the taxpayer!
Of course, I could probably have knocked it out for vastly less (and even subcontracted a designer to make it look less pig-ugly), but much of the cost probably came about through the fallacy of the efficiency of internal markets: they needed information from HMRC which charged them £x for providing it, they needed information from the DTI which charged £x for providing it, and so on and so forth.
This business of one component of some overarching organisation (such as HMG) charging another component thereof for sharing information with it is ludicrous: if they have the information, and can tell the other lot how to access it, the cost of providing it has been about two minutes of one person's time sending an email with a link, or possibly slightly longer explaining how to access it over some internal Government network, or at worst the time taken to burn a set of those data DVDs they're so fond of leaving on trains.
Instead, they take the cost of aggregating the information (which they had to do anyway, usually by law) and then try to claw that cost back by charging the other component some part thereof, calculated according to some formula that probably doesn't make any sense in the first place, given that they don't know in advance which components might find a use for that data, and therefore can't calculate its value in advance.
If a Government department charges the "internal market" rate for providing data to another Government department, and at a later date finds that a bunch of other departments also want to make use of it, do they then give a refund to the first department that wanted it, given that the cost has now been spread across many "customers"?
Or, given that the cost of aggregating the information was always going to be there, is it a case of robbing Peter to pay Paul, with additional accountancy and administrative costs thrown in at every step of the proceedings?