Well, I think that as we look at oil prices, I think that we'd be a little too narrow in our view of the company to just look at oil prices in and of themselves. As oil prices are going down because of sluggish economic demand, you're going to see a push downward in margins regardless of what happens to oil prices. If oil prices are falling because there's a glut of oil on the market, that's quite another scenario. I think that when we look back a year ago at this time, we saw better economic conditions a year ago at this time, and oil was falling because there was a glut of it on the market. I think as we look at the overall market today, oil prices are down. But it feels like the economy is a little softer than it was a year ago. So, I mean, forgive me, I think that as we look at the overall market, certainly with what we've seen with the drop of oil this last year, a year ago at this time being in the mid-$70s a barrel and during the fourth quarter in the low $40s a barrel and today being around $30 a barrel, we're certainly not going to see the fall of oil prices this year in 2016 as we saw in 2015, because that means oil would be down to like $2 a barrel. But I think that that will certainly put pressure on margins of those products that benefit most from the U.S. differentiation of gas prices and global crude prices. That would be MTBE, ethylene, and first-line ethylene derivatives, if you will. And I think it also should allow us probably on a quarterly, not on a yearly basis, but on a short-term basis, to be able to capture some of the margin on falling raw material prices, as we saw in the fourth quarter. We saw some pretty strong MDI margins compared to what we're expecting because of falling raw material prices. We were able to keep some of that added margin. So, I think, again, it's going to be a combination of lower raw materials. It's going to be coupled with economic growth and how that will determine the economic vitality will determine how well we're able to keep that expanded margin.