There is no shortage of anecdotes regarding the fragile state of affairs in global equity markets, but sticking to just the facts, market participants know that the S&P 500 and the Dow Jones Industrial Average each shed more than 5 percent last week while the Nasdaq Composite bled 6.3 percent. Apple Inc. proved problematic for all three major U.S. indexes because the iPad maker is the largest component in the S&P 500 and the Nasdaq as well as being a member of the Dow.