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The Day's Poster

The Wednesday, September 9 session at a glance: the Nasdaq 100's hundred companies drawn as one city skyline.

Broad Selloff: 78 Nasdaq 100 Stocks Fell; Communication Services Led, Industrials Lagged

Sep 9 ClosePoster Archive

Nasdaq 100− 0.29%

The Nasdaq 100 Skyline

  • Building Width: Market Value
  • Height: Daily Change
  • Above the Horizon Rose, Below Fell

Each building is a Nasdaq 100 company; the buildings stand in sector districts, from the strongest district to the weakest. Tap a building or step through with the arrow keys.

Highlights

Up and Down
2378
Strongest Sector
+ 0.05%
Communication Services
Weakest Sector
− 3.23%
Industrials
Other Indices
S&P 500− 0.46%Dow Jones− 0.75%Russell 2000− 1.37%

The headline is built from these numbers by fixed rules: a broad day when at least 70% of the companies that moved went the same way, a narrow day when the index went one way and most companies the other; flat when the Nasdaq 100 closed within ±0.10%. The sector order comes from the districts' changes.

Changes are the Sep 9 close against the Sep 8 close; after-hours trading is not included.

A building's width is proportional to the square root of the company's market value at the Sep 9 close (using today's share count): the square root keeps the gap of several hundred times between the largest and smallest company readable.

Districts are GICS sectors; sectors with fewer than five companies are grouped as Other Sectors. A district's change is its companies' average weighted by market value.

The indices are tracked through their funds (QQQ, SPY, DIA, IWM); changes are fund price changes, excluding dividends.

Breadth is counted with today's Nasdaq 100 member list; on a past day a few companies not yet in the index may be counted and departed ones left out.

Alpaca · SIPUpdated 11:39 NY15 Minutes Delayed

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