Oprah Winfrey has lost nearly $117 million since first investing in Weight Watchers last October.

When the media mogul announced her new involvement with the diet company last year, which included a purchase of 10 percent stake and a seat on the board of directors, Weight Watchers stock shot up 300 percent within weeks.

Since then, it has dropped back down to earth, costing the company nearly $1 billion in market valuation, according to Forbes. The dramatic losses led to the resignation of CEO Jim Chambers on Monday.

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Chief Financial Officer Nicholas Hotchkin and two board members will now run the company on an interim basis.

Weight Watchers’ stock fell by 5.4 percent after hours Tuesday to $9.80, well below the high-water mark of $28 last November, and only slightly higher than its $6.79 price before Winfrey announced her partnership with the company. Investors now value it at a little more than $600 million.

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“Board members, including Oprah Winfrey and myself, will be actively involved in the search for a new CEO, and look forward to working with her or him in shaping the future of Weight Watchers,” Weight Watchers Chairman Ray Debbane said in a statement.