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What: Shares of Apollo Education (NASDAQ:APOL) crashed on Wednesday after the company reported fiscal second quarter earnings. As of 11:30 Wednesday morning, the stock was down more than 23%.

So what: Apollo reported revenue of $578.6 million for the quarter, down 14% year-over-year and short of analyst estimates by $6 million. Degreed enrollment at the University of Phoenix fell 14.6% year-over-year, with revenue from the segment declining by 17.9%. University of Phoenix makes up the bulk of Apollo's revenue.

Operating profit turned negative for the quarter, with Apollo reporting a $54 million operating loss compared to a $10 million operating profit during the same period last year. Profitability at the University of Phoenix disintegrated, with operating profit from the segment falling from $86.6 million during the second quarter of last year to just $1.4 million in the most recent quarter.

Apollo guided for fiscal 2015 revenue between $2.63 billion and $2.68 billion, well below the $3 billion in revenue Apollo generated during fiscal 2014. Apollo expects operating income between $200 million and $230 million, excluding special items, during fiscal 2015, continuing the company's multi-year decline in profitability.

Now what: CEO Greg Cappelli had this to say about Apollo's quarter: "While we faced challenges in the second quarter, we believe Apollo Education Group has the right long-term strategy in place. In a time of unprecedented change in the higher education industry, we are focused on enhancing outcomes through a deep understanding of student and employer needs. This includes differentiating University of Phoenix through its program-based colleges and diversifying our organization with the expansion of Apollo Global and other targeted growth initiatives. We are aligning education to careers, offering students tangible skills and helping employers develop a high-performance workforce."

Apollo has been in decline since 2010, with Apollo's guidance for 2015 operating profit representing just one-fifth of the company's operating profit during that peak year. For-profit education is a business subject to heavy regulation, and the bonanza of the past, when Apollo generated operating margins as high as 30%, appears to be over. The stock looks cheap based on current earnings, but there's no telling how much further profitability will decline.

Timothy Green has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.