Say you want to get some extra exposure to the movement of Apple's stock, but you don't want to buy Apple directly. In that case, consider some surprising names with the highest correlation to the tech giant's share performance.
In the past year, Illinois Tool Works (ITW) has a 0.61 correlation to AAPL—the highest of any stock in the S&P 500. That means Apple and ITW tend to see their two stocks both move up -- or both move down together on the same day.
While it might seem surprising that the maker of Rain-X and Slime tops the list, the second-biggest business for ITW is its Test & Measurement and Electronics segment, at 15 percent of revenue, just behind its largest piece: auto components.
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The numbers are based on an analysis from Kensho, a market data product.
Other big tech names are high, as well, such as Facebook (FB) and Texas Instruments (TXN), both at 0.55. Those make sense, given that Facebook is another huge tech firm, and TXN is a major supplier to Apple. Those reality checks make the following names even more surprising: Boeing (BA) at 0.57, Wells Fargo (WFC) at 0.58 and Blackrock (BLK) at 0.55—stocks that most people wouldn't expect to move so tightly with Apple.