Major U.S. stock indexes dropped by more than 1 percent Tuesday in what amounted to the worst single trading session for American markets since October. The drop appeared to vindicate worries that the record-breaking U.S. equities may be vastly overvalued.

The Dow Jones Industrial Average (DJI) tumbled by nearly 300 points, or 1.3 percent, the S&P 500 (GSPC) fell as much as 36 points, or 1.5 percent, and the Nasdaq Composite (IXIC) slipped nearly 122 points, or more than 2 percent, at certain points in the trading day. The dollar index (DXY), measured against a basket of currencies, dropped below 100 for the first time in six weeks.

Analysts attributed the flop to the stalled approval of Congressional Republicans’ new health care bill, as well as dampened expectations for much of President Donald Trump’s promised agenda, such as the $1 trillion stimulus package he proposed while on the campaign trail.

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“Our view is that the market is taking a pause, and ultimately many of the pro-growth policies that are expected from this administration will get done,” said Chris Zaccarelli, the chief investment officer for the wealth management firm Cornerstone Financial Partners. “In the meantime, we are going to be in for some volatility until we get more clarity from the Congress on what will get passed and when it will happen.”

Others, like LibertyView Capital Management LLC President Rick Meckler, attributed the market panic to politicized distractions within the federal government.

“Yesterday’s political action, particularly the [Federal Bureau of Investigation Director James] Comey testimony, I think pointed to the fact that there could be a lot of drawn-out political infighting that could delay some of the pro-business ideas from being passed,” Meckler told Reuters Tuesday. “I think periodically investors become nervous about it and look to take profits on what has been a big move to this point.”

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Beyond Capitol Hill, the drop in equity values followed some startling market news. The largest portion of fund managers since 2000—at more than a third—believe global stocks were priced above their real values, with more than four in five seeing the U.S. equities market as the most overvalued, according to a recently-released survey by Bank of America Merrill Lynch of investors in charge of a collective $592 billion.

The three main U.S. indexes have repeatedly toppled record highs since Trump’s election, stoking fear that the numbers could be, as Seth Klarman of Baupost Group, which manages $30 billion, told the New York Times in February, “perilously high valuations.”