I think it's a great question, sir.
The first accident happened. The trend line, if you look on the slide with NOD, did not give us any outlier that we had an issue in infrastructure, and we'll see what we find out at the end. The normal reaction is to find out. We send in our own experts to find out exactly what happened. If we need to slow down a piece of track because we don't understand it, we look at the type of rail, we look at who manufactured the rail. Do we have other issues? If it was a railcar, we look at who loaded it, how it was loaded, and we do a lot of homework. These happened so quickly to us that we didn't get a clear answer on the first derailment, but after the third derailment there was no question that we had to react even without knowing the cause. That's why we slowed the speed down, did even more inspections than we had before. We wanted to make sure we understood it. That's what we've done.