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September 17, 2026 · market close

Micron and Nvidia Push the S&P 500 to a Large Move as the Dow Lags Behind

Chip and megacap strength drove the S&P 500 and Nasdaq 100 to their biggest gains in months while Caterpillar and Goldman Sachs did the heavy lifting for a more modest Dow advance.

The S&P 500 closed at 7,637.76, up 85.95 points, or 1.14%, on the day. Breadth was solidly positive, with 294 of the index's 502 members finishing higher. Concentration was moderate at 35%, meaning the gain was not the work of a handful of names alone even though the largest ones did plenty of work.

The S&P 500 through the session

Nvidia led all contributors with 15.5 points on a 2.54% gain, followed by Apple at 8.02 points, and Microsoft and Micron tied at 6.57 points each. Micron's contribution came on a 5.5% jump, the largest single-stock move among the day's leaders. Amazon added another 6.05 points. On the other side, Berkshire Hathaway was the heaviest drag at negative 2.4 points on a 2.04% decline, with Salesforce, Verizon, T-Mobile and Netflix rounding out the small list of laggards.

S&P 500 attribution map, cell size = points contributed

The Dow

The Dow closed at 51,778.00, up 316.1 points, or 0.61%. Breadth was strong at 21 of 30 members higher, but concentration ran to 69%, well above the S&P's reading, meaning fewer stocks did more of the lifting. Caterpillar was the standout, adding 93.85 points on a 2.02% gain, with Goldman Sachs next at 78.93 points. Microsoft, Nvidia and Amazon also contributed, echoing their roles in the broader index. Salesforce was the clearest drag, subtracting 44.81 points on a 3.01% decline, followed by Boeing at negative 29.18 points. This is where the Dow's story splits from the S&P's: industrial and financial names, not chipmakers, did the heaviest lifting for the blue-chip index, even as Salesforce weighed far harder here than it did on the broader market.

The Dow through the session Dow attribution map, cell size = points contributed

The Nasdaq 100

The Nasdaq 100 closed at 29,446.98, up 501.92 points, or 1.73%, the sharpest percentage move of the three indices today. Breadth was positive but less broad in proportion, with 63 of 101 members higher. Nvidia again topped the list with 82.82 points, followed by Apple at 42.32 points and Micron at 36.35 points on that same 5.5% jump that showed up in the S&P numbers. Amazon and Microsoft filled out the top five. T-Mobile was by far the largest drag, down 6.65 points on a steep 5.57% decline, with Walmart, Netflix, Comcast and Lumentum also in the red. The divergence from the S&P here is straightforward: the same chip and megacap names that lifted the broader market did so with more force inside the Nasdaq 100's narrower, tech-heavy composition.

The Nasdaq 100 through the session Nasdaq 100 attribution map, cell size = points contributed

The sectors

Ten of eleven sectors closed higher. Technology led with a 2.25% gain, adding 4.13 points, while Consumer Discretionary and Utilities followed at 1.10% and 0.87%. Financials and Communication Services were the only sectors to close lower, at negative 0.11% and negative 0.59% respectively.

The 11 sectors by move, top contributor named

Technology's advance was led by Nvidia, which contributed 0.68 points to the sector on its 2.54% gain, consistent with the chipmaker's outsized role across every index today.

Technology: what moved it

Communication Services was the day's weakest sector, dragged down by T-Mobile, which subtracted 0.29 points on its 5.57% decline, the same stock that weighed most heavily on the Nasdaq 100.

Communication Services: what moved it

Against the past year of sessions, today's S&P 500 move sits at the 93rd percentile and the Nasdaq 100's at the 92nd, both qualifying as large moves. The Dow's 79th percentile move was firm but falls short of that threshold, another marker of how much more concentrated the day's gains were in Nvidia, Micron, Apple and their megacap peers than in the broader industrial and financial names that anchor the blue-chip average.

The numbers

From Babylon Burns

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Goldman Sachs Drags the Dow Lower While Chip
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Compiled by the WMTMT attribution engine from the session's official data · built by the founders of Babylon Burns