Billionaire investor Stanley Druckenmiller says the stock market is in a Fed-fueled 'raging mania' that could lead to a 5-year hangover

• Stanley Druckenmiller told CNBC on Wednesday that the stock market was in a "raging mania" fueled by the Federal Reserve.
• The billionaire investor said that the Fed did a "great job in March" but that the recent market rally had been "excessive."
• "Look, everybody loves a party ... but inevitably after a big party there's a hangover, and right now we're in an absolute raging mania," he said.
• He added that he was worried that the US could easily see 5% to 10% inflation in the next four or five years.
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The billionaire investor Stanley Druckenmiller told CNBC on Wednesday that there was a "massive, massive raging mania in financial assets" fueled by the Federal Reserve that had not spilled over onto Main Street and could lead to challenges for the next five years.

"I have no clue where the markets are going to go in the near term," Druckenmiller said. "But I just want to remind people that there is no valuation support because we drop 10%. That hasn't mattered, because we're so far out the valuation realm with the Fed doing what they're doing."

He added, "I would say the next three to five years are going to be very, very challenging."

The head of Duquesne Family Office said that Fed Chair Jerome Powell did "a great job in March" after cutting rates but that the follow-up market rally had been "excessive." Even though Tuesday marked the S&P 500's third straight day of losses, the index has still rebounded roughly 48% from its March 23 intraday low.

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"Look, everybody loves a party ... but inevitably after a big party there's a hangover, and right now we're in an absolute raging mania," he added.

One example of the mania is the performance of large companies splitting their stocks. Druckenmiller said that while these splits create no value, the stocks of the companies continue to go higher — sometimes by 50% — after them.

He also said that for the first time in a long time he was worried about inflation.

"We actually have the chairman of the Federal Reserve with a $3 trillion deficit out lobbying Congress to do more spending and guaranteeing those of us on Wall Street that he'll underwrite it," Druckenmiller said. "I think it's dangerous. I think we could easily see 5% to 10% inflation in the next four or five years."

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