The fate of the S&P 500 index — used by investors as a barometer for the health of corporate America, and cited by presidents as a measure of their handling of the economy — often comes down to just two companies: Apple and Microsoft.This means it’s hard to invest in the U.S. stock market, such as through a 401(k) or pension plan, and not be highly dependent on the fate of the two tech giants. More than $15 trillion in assets, from pension funds and endowments to insurance companies, are linked to the performance of the S&P 500 index in some way, according to S&P Dow Jones Indices, with more than 10 cents of every dollar allocated to the broad index flowing through to Microsoft’s and Apple’s market valuation.It is a phenome …
