"Dow falls 140 points at the open as Boeing, Caterpillar deliver disappointing results" (BA; CAT)

Caterpillar being the more troubling indicator of future economic conditions.
From MarketWatch:

U.S. stocks on Wednesday opened firmly lower, with weak results from Boeing Co. BA, -0.59% and Caterpillar Inc. CAT, -4.11% weighing on the Dow and the broader market. The Dow Jones Industrial Average DJIA, -0.27% declined 140 points , or 0.5%, to reach 27,205, the S&P 500 index SPX, +0.06% slipped 0.3% to 2,997, while the Nasdaq Composite Index COMP, +0.09% retreated 0.3% to hit 8,230. Aerospace giant Boeing Co. swung to a loss in the second quarter, while Caterpillar, the manufacturing and construction-equipment giant produced weaker-than-expected results....MORE 

With the divisor on the DJIA at  0.14744568353097, each dollar move in the component stocks is worth 6.782 points on the index.
Pseudo-sophisticates will tell you what an inferior index the DJIA is but it tracks closely enough with the S&P 500—r=.90-.97 depending on the time frame—that we prefer it as shorthand for "the market".