You can call it an honest mistake in that they didn't try to hide their tracks. Though maybe it's just a feeling of impunity.

Had they put the "to be developed or found" on the top of the other quantities it would have been difficult to realise that the amount was just so that the total amount of crude oil is a constant.

Of all the ways of organizing banking, the worst is the one we have today — Mervyn King, 25 October 2010