Let's Just Skip Ahead. A lot went wrong for markets today.

The Dow Jones Industrial Average sank 698 points, or 1.3%. The S&P 500 dropped 0.9%. The Nasdaq Composite fell 1%.

The bond market was a major reason stocks took a tumble. Bonds sold off again on today despite rallying Wednesday on the Treasury's announcement that it was raising buybacks for long-dated bonds. Treasury yields rose on Thursday, with the 30-year Treasury bond reaching 5.25% and the 10-year reaching 4.7% (bond prices and yields move inverse to each other).

"Treasury buyback operations may improve market liquidity and help reduce some near-term volatility in the long-dated Treasury maturities, but we do not believe the Aug. 19 announcement materially changes the longer-term outlook for interest rates," writes Luis Alvarado, co-head of global fixed income at Wells Fargo Investment Institute.

Higher bond yields translate into higher borrowing costs, which is bad news for equities. Tech companies are especially sensitive to higher rates, particularly now that hyperscalers are spending billions on the AI buildout.

It doesn't help that two strong stocks-Moderna and Walmart-got pummeled today for totally different reasons. Moderna shed 24%, marking its largest percent decrease on record, according to Dow Jones Market Data. Walmart was down 9.2%, its biggest percent decrease since 2022. Moderna was the worst performer in the S&P 500 today and Walmart was the second-worst; Walmart was the Dow's worst stock today.

I'll get to Moderna further down. For Walmart, investors didn't like what they saw in the company's second-quarter earnings report. Walmart's U.S. comparable-store sales growth slowed, partially because new drug price caps lowered sales in Walmart's Health and Wellness division. The company also issued an underwhelming outlook for the rest of the year, which helped spread the pessimism across to other retail stocks. The SPDR S&P Retail ETF dropped 2.4% on Thursday.

Bitcoin was the day's silver lining. The cryptocurrency gained 4.9% on Thursday and hit its highest intraday level since June 1. Crypto bulls have President Donald Trump to thank. The president has joined ranks with crypto executives to urge Congress to pass the Clarity Act, an industry-friendly bill.

All in all, it was the kind of day that made you want to pack up your bags and move to Australia. But don't worry, there's always tomorrow.

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The Hot Stock: Nordson Corporation +8% The Biggest Loser: Moderna -23.6%

Best Sector: Energy +0.4% Worst Sector: Consumer Staples -1.9%

What's Moderna Got to Do With it?

A lot, apparently. Moderna's whopping 177% jump on Wednesday after announcing positive results for its cancer vaccine caught short sellers off guard, causing ripples across other sectors.

Moderna's short interest hovered at around 13.7% of the float, notes my colleague, Mackenzie Tatananni. The surge rendered paper losses of about $5.5 billion for short sellers, helping drive a short squeeze-and pressuring hedge fund managers to sell off other stocks to cover their positions.

"As those positions surged, many hedge funds had to cut risk elsewhere, often by liquidating their top-performing, highest-conviction stocks," Mackenzie adds, such as AI and infrastructure stocks.

The short squeeze contributed to Moderna's 177% increase, but a lot of it was genuine optimism about Moderna's melanoma vaccine announcement. A trial of 1,100 patients found that a treatment combining Moderna's intismeran autogene vaccine and Merck's blockbuster immunotherapy drug Keytruda is more effective than Keytruda alone in preventing the recurrence of skin cancer, helping people stay cancer-free for longer after having their melanoma removed.

This is the first Phase 3 trial success for a cancer vaccine. And while there are still various obstacles ahead before the vaccine secures final approval and commercialization, it marks a move into next-generation, personalized oncology treatments that could be easily scaled into a multibillion-dollar business for Moderna, Mackenzie notes.

The Calendar

BJ's Wholesale Club Holdings report earnings tomorrow.

S&P Global releases both its Manufacturing and Services Purchasing Managers' Indexes for August.

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