On some of the main drivers of costs, if you look at the low end of the PBO range, to some extent it's not that different from the estimate of the government. The biggest assumption difference is when capacity constraints are hit, and the extent to which the government will accommodate that by increasing density versus construction. We've made it quite clear in the paper when that tipping point occurs. That's why if we understood where those constraints were from the government side, we could be in a better position to reconcile differences.
On March 16th, 2011. See this statement in context.