On the historical data, we're looking at gathering information about actual emissions, and we model where we need to, but essentially we're gathering information about what was actually emitted from those sectors that were captured.
In terms of the degree of confidence, because we look at it every year and we're constantly revising to make sure that we've captured all of the information that is available, the level of confidence improves with every year, I guess you could say, but I can't give you a number.