It's a good question. I have a couple of points.
The $6 billion is the liability for the benefit that has been earned to date. This is the amount that employees have earned under previous collective agreements; it is their earned right to receive that, and no one is going to take it away.
Your question, I believe, is around the savings on a go-forward basis, which we're estimating—and “estimate” is the key word—at about $500 million once per year, once all is said and done. The reason I say “estimate” is you're quite right, it is a negotiation. There are almost 20 agreements that still need to be negotiated, and that will take time. I cannot commit to what the exact savings will be because, you're absolutely right, it is a negotiation and it's still to take place. That's why I have used the words “estimated $500 million” or roughly $500 million. But the negotiations will occur as agreements expire. That will happen over the next couple of years.
The $6 billion liability is what employees have earned to date, roughly, for provisions under existing collective agreements, and that's not being touched.