The S&P 500 represents the broad US equity market. It is the bogey for countless herding asset managers and is seen as the professional's index as opposed to retail's Dow. But, a scratch under the surface of the magnificent 500 company index shows it to be extremely top-heavy. From Intel to Apple, the following 10 companies represent over 20% of the 500 name index - and these 20 stocks account for 42% of all S&P 500 margin.
[5]
Source: Goldman Sachs