2026.5.20 US Stock Daily | Oil Crashes Through $100, All Three Indexes Bounce

Trump said US-Iran negotiations have “entered the final stage.” WTI crude dropped from $107 the previous day straight to $99.77, down 7.4% in a single session. Shipping data backed this up: between May 11 and 17, at least 54 vessels transited the Strait of Hormuz, compared to just 25 the week before. The core thesis behind the earlier oil price surge was a prolonged blockade of the strait. Now that transit volume has doubled, that thesis is starting to crack.

The chain reaction from falling oil was straightforward. Inflation expectations cooled, the 10-year Treasury yield dropped roughly 9 basis points to 4.57%, and the bond market loosened its grip on equities. The S&P 500 closed at 7,432.97 (+1.08%), Nasdaq at 26,270.36 (+1.54%), and the Dow at 50,009.35 (+1.31%), reclaiming 50,000. The VIX fell to 17.44.

Sector divergence was stark. Energy (XLE) dropped 2.43%; nearly everything else rallied. Tech (XLK) gained 2.25%, consumer discretionary (XLY) rose 2.53%. Semiconductors led the charge — the Philadelphia Semiconductor Index surged 4.5%, AMD soared 8.1%. Samsung’s union announced it would postpone its strike and move to a wage vote, easing fears of memory supply disruptions and funneling capital into chip stocks. Small-cap IWM climbed 2.52%, with risk appetite broadly restored.

The after-hours headliner was Nvidia’s Q1 earnings. Revenue came in at $81.6 billion, up 85% year-over-year, with data center contributing $75.2 billion. Q2 guidance of $91.0 billion beat expectations across the board. The board authorized an additional $80 billion in buybacks and raised the quarterly dividend to $0.25 per share.

The numbers were flawless, yet the stock slipped 1.3% after hours. Q2 guidance implies 11.5% sequential growth — the rate of acceleration is decelerating at the margin, even though the absolute figures remain staggering. The market had already priced in a beat; what matters now is the magnitude of the beat. Tomorrow’s regular session is where the real price discovery happens.

On Polymarket, the probability of a “permanent US-Iran deal by end of May” sits at just 22%. The market was willing to knock 7% off oil on a single Trump remark, but very few are betting an actual deal gets signed. Oil is a political sentiment trade right now. The half-life of any Trump statement might be a matter of days, and any negotiation setback could send prices right back above $100.

Today’s rally was built on a single variable: oil. Trump has reversed course on Iran too many times to count. The moment strait transit data contracts or talks hit any snag, the rally’s logic has to be recalculated. The other window to watch is Nvidia’s price action during tomorrow’s session — if a Q1 this strong still can’t sustain a move higher intraday, the near-term ceiling for tech is right there.