I think I actually responded to that question. Because the railway operating certificate is not specific about the obligations to be imposed, it's very difficult to come up with a cost estimate.
What I did say--and I think it would be echoed by my colleagues--is that the incremental cost is the cost of inspectors, compliance, and engineers looking at maintenance inspection records to validate accuracy. The degree of rigour is not outlined in the railway operating certificate, so you can't estimate it. But it's an incremental cost to what we're doing today, assuming the railways will even let you do it. I've said before that this is not information they would typically allow us to look at, because it's not our information; it's theirs.