Despite the sluggish economy, the Olsen Twins still managed to sell $1 billion worth of clothing!

Mary-Kate and Ashley Olsen's clothing companies, The Row, Elizabeth & James and Olsenboye have a combined total of $1 billion in retail sales through their company, Dualstar.

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The twins started Dualstar when they were just 6 years old, but they really broke into the fashion industry with a line at Walmart when they were 12.

And we were really designing it. It would be jeans, a bit bohemian, or with a little blazer. It was really fashion-forward, Mary-Kate said.

The twins have since moved up in the fashion industry and have big plans for their future.

I want to run a studio. I'd probably like to manage other people on their brands. It could be an artist. A young designer. It could be an existing brand, Ashley states. Mary-Kate added, The thing about us is we think big. Huge.

Related article: Ellen Gives The Olsen Twins Oversized Sunglasses!

Mary-Kate and Ashley are up for a CDFA award this year, their first nomination ever. Other designers nominated for the Swarovski Award for Womenswear category are Joseph Altuzarra and Prabal Gurung.

What do you think of Mary-Kate and Ashley's fashion empire?

Photo courtesy of Fame Pictures

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