If I look at the significant drivers, first in the sales front versus last year, we did see very strong Aerospace growth, and our Cast and Forging increasing by roughly 20%. We saw some growth of roughly 5% in our Aero Fasteners. And again, this is driven more by our expanding market push versus growth in our core Fasteners.IGT saw roughly a 10% increase versus last year. And this basically was in the Forging segment. And we continue to see solid general investor growth of roughly 30% versus last year. On the flipside, as we did in Q2, continue to see that comparison year-on-year, a drop on our seamless extruded pipe, showing significant decrease from last year of roughly 35%. And then rounding out and comparing kind of an apples-to-apples, we saw a decrease in our contractual material pass-through of roughly $5 million and we saw a higher nickel selling price of roughly $27 million. If I look sequentially, we did continue to see Aerospace growth of roughly 5%. I think we've now basically eliminated that disconnect we have from the de-stocking between our customer schedules and the build rates in that Casting and Forging world. So we're kind of in alignment now with where we should be. We did see some small growth in our seamless pipe but again, this was off a very significant reduced space. And we saw a stable volume in IGT and our Fastener distribution sales also remained flat. If I look at the key drivers on operating income, on year-on-year, we did see solid drop through on our Aerospace growth in both Cast and Forgings. But again, Forgings also continue to see their margin impact of replacing the lower pipe sales with strong general and industrial sales. And to the same extent, we're seeing in the Fastener impact, we are replacing last year the distribution of the 787 sales that hit our numbers last year with general, industrial and that expanding Fastener Products, but again, we'll get into it as we look at the Fasteners.
If you look at the sales profile for the company, same trend we saw last quarter. Aerospace continues to make up a large piece of the puzzle, with a score of 57% of our sales versus 55% last year. In the flipside, power accounted for roughly 23% versus last year's 26%. And then general and industrial makes up a difference going from 19% last year to 20% this year.Moving on to the segments now. Investment Cast Products saw sales growth compared to last year of 18.3% going from just under $455 million last year to roughly $538 million this year. And operating income increased by roughly 24.2% this year going from $137.5 million last year to $171 million this year. We got solid margin expansion going from 30.2% last year to 31.8% this year. If I look at the key drivers in the Investment Cast segment, looking at sales year-on-year, certainly the main story line is a solid Aerospace growth. We saw a 30% increase versus last year. The two primary drivers on this on both fronts, we saw the OEM demand increased by roughly 35%. And again, I think in this Casting, we have finally close that gap on the disconnect we had between the schedules and the build rates and we did see a rebound in the aftermarket with the roughly a 25% increase versus last year. On the flip side, we also saw basically flat sales in IGT and we did see a small increase in contractual material pass-through versus last year of only $3 million. If I look at the sales sequentially, on Aerospace, we did continue to see sequential growth. We saw a roughly 10% versus last quarter and IGT saw modest growth but as the stories kind of in all year, it moves around, this particular growth was seen by the growth in the aftermarket. And again, it kind of offsetting the reduced OEM deliveries.
And IGT has been kind of all throughout this year, it's been a trade-off. Market share help offset kind of declined early in the year. Now we've got the aftermarket offsetting the OEM. It's basically to keep us relatively flat throughout the year.Operationally, year-on-year primary drivers as you can imagine is the incremental leverage on the Aerospace sales. We saw a roughly a 40% drop. And I think it's important to note to that this point in time that in the Castings, it is really the only segment at this point that we are seeing comparable growth. So if I go back to where we were last year, it's the same products, just growing at a larger rate and kind of see the value of that when we get that growth coming in our core products and how we can drop that through. We also continue to see solid performance improvements. It's an area we continue to attack. In this particular segment, that variable cost is a big piece of the puzzle. It's not material. We've seen solid productivity gains across our operations. We've seen a decreasing variable hourly rate and we continue to utilize in some of our operations, we've continued to grow Mexico substantially over the course of the last 12 months. So I think that we are -- given this growth, focused on continuing to attack that cost model and there is still a number of opportunities so that when we can face available to us moving forward. If we look forward at Investment Cast, I think that if you look at the next 12 to 16 months, we certainly have some large catalysts that are out there in the horizon. Even though we are now matched up, I think as we move forward, we have to support the RE announced increased bill rates on 777, 737 and the A320. And for us, a good timing is to take those announced bill rates and back up roughly four to six months. So if you kind of look at the announcements in back up, that's when we should expect to see that acceleration. Read the rest of this transcript for free on seekingalpha.com