It's the latest example of relatively younger companies wielding more of an influence on the overall S&P 500. For example, at the end of 2010, ExxonMobil was still atop the S&P 500 market cap rankings, with Apple hot on its heels. Chevron, Procter and Gamble, IBM and AT&T were also fixtures in the most valuable companies in the index.
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Fast forward to today, where Apple has built up such a commanding lead in the market value category that it dwarfs both second- and third-place companies Google and Microsoft, respectively. In fact, Apple is as big as both Google and Microsoft combined.
Replacing companies like AT&T and Procter and Gamble are a pair of banking behemoths, Wells Fargo and JPMorgan Chase. And of course, Facebook kicked Wal-Mart out of the top 10 with its recent run.
These are larger shifts in the business landscape of America's publicly traded companies, but for companies like Facebook, the disruption and seismic shifts they are creating can happen in much shorter timeframes. Whether they have the endurance to be a part of the bigger picture long term remains to be seen.
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