Here’s why the Dow’s drop is mostly Boeing’s fault

That put the stock on track to suffer its worst one-day performance since it dropped 8.8% on Oct. 26, 2022, when it announced earnings that fell short of analysts’ expectations.

Also read: Alaska Airlines and United ground their Boeing 737 Max 9 jetliners after in-flight blowout.

The stock’s price decline of $20.37 soon after the open would cut about 134 points off the Dow’s

price, while the Dow fell sank 185 points, or 0.5%. Meanwhile, the S&P 500 index

tacked on 0.2% and the Nasdaq Composite gained 0.7%.

The Dow is a price-weighted index, which means stocks with higher prices have more influence on the index’s price than lower-priced stocks. In contrast, the S&P 500 and Nasdaq indexes are weighted by market capitalization, meaning the more market value the company has, the more influence it has on the indexes’ prices.

Boeing’s stock’s current price makes it the 10th most influential among the Dow’s 30 components. The most influential is UnitedHealth Group Inc.’s stock
UNH,
while the shares that have the least influence are those of Walgreens Boots Alliance Inc.
WBA.

With a current market cap of about $138.3 billion, Boeing’s stock is the 58th highest-valued in the S&P 500.

Every $1 move in any Dow stock will move the index by a little less than 7 points. But a 1% move in UnitedHealth’s stock would the Dow by a little more than 35 points, but a 1% move in Walgreens’ stock would have a little less than a 2-point effect. A 1% move in Boeing’s stock moves the Dow a little more than 16 points.

Meanwhile, Alaska Air’s stock is a component of the Dow Jones Transportation Average
,
which like the Dow industrials is also price-weighted, but uses a different calculation. With Alaska Air’s stock down 4.2%, that would shave about 10 points off the price of the Dow transports, which fell 43 points, or 0.3%.

Shares of Spirit AeroSystems Holdings Inc.
SPR
tumbled 13.8% in the premarket, but they are not components of the Dow or the S&P 500.