Jessica Simpson's design line set to make $1 billion for the present year: She may have lost some of her lustre when it comes to record sales, but Jessica Simpson reigns supreme in the fashion world. Her empire is projected to make history this year, by becoming the first ever celebrity fashion line to earn one billion dollars in annual sales.

The singer-turned fashion designer's clothing line raked in an astonishing $750 million dollars in sales last year, making it the top selling celebrity clothing empire.The 30-year-old Texas native launched her Jessica Simpson Collection in 2007 with a line of handbags, shoes and boots.

She has since expanded it to include watches, clothing, cosmetics, luggage, bathing suits, and fragrances, which are all sold in major department stores across America. According to fashion blog thefashionistaforum.com her sales have risen by almost a quarter in the last 12 months. That would put her in the same league American fashion titans Michael Kors, Ralph Lauren, Calvin Klein, Vera Wang and Donna Karan.

But a humble Jessica says she is surprised by the line's runaway success. 'I never thought I'd be some fashion mogul,' Jessica revealed in an upcoming interview with New York Magazine. She also told the magazine she plans to launch new ready-to-wear and career separates lines.

In the interview, Jessica also opens up about her engagement to former NFL player Eric Johnson, and described his marriage proposal. 'It felt great for somebody to be on his knee and I had to sit on that knee because I was so excited and overwhelmed,' she said. Jessica has not yet revealed a wedding date -- or who will be designing her wedding gown.