Alcoa on Thursday posted quarterly earnings well below Wall Street's expectations, as high-growth aerospace and automotive materials segments could not soften the effects of low commodity prices.
The aluminum maker posted adjusted third-quarter earnings of 7 cents per share on $5.57 billion in revenue. Sales dropped about 11 percent from the previous year.
Analysts expected Alcoa to post earnings of 13 cents per share on $5.65 billion in revenue, according to a consensus estimate from Thomson Reuters. The stock dropped about 5 percent in extended trading.
The metals maker announced late last month it expects to separate into two publicly traded companies by the second half of next year. After the results, Alcoa CEO Klaus Kleinfeld stressed the importance of the split, saying the company needs to focus on cutting costs to mitigate commodity headwinds.
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"All in all, we have made the company more competitive, more resilient and in this light I think we need to focus on those things we have in our own control and that's what we are doing," he said on CNBC's "Closing Bell."
Alcoa will split into "upstream" and "value-add" businesses, with one housing its legacy aluminum production and the other materials manufacturing for industries such as automaking and aerospace. The transition comes amid a divergence of the two industries and a big dip in the price of aluminum amid a commodities crunch.
"This is not about short-term optimization. This is really long-term, well thought through and put in place strategy," Kleinfeld said.
He touted progress in the value-add segment, singling out growth in aerospace. Alcoa's aerospace, automotive and alumina sales jumped 10 percent from the previous year.
Kleinfeld stressed his view that the upstream business will be strong after the split, despite the growth disparity between the two segments. He said investors need to understand the company will not be just aluminum production.
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Alcoa cut its forecast for the 2015 global aluminum surplus to 551,000 tonnes from a previous estimate of 762,000 tonnes. The company said it expects a deficit in the market in 2016, but did not specify how much.
Kleinfeld also told CNBC that slowing growth in China was not concerning, as Alcoa has already lowered its expectations there.
"You have to put it into perspective. It's not like falling off a cliff," he said.
Alcoa shares have taken a nosedive this year, down more than 30 percent. However, they have climbed about 15 percent since the split announcement.