As the market turmoil continues, companies that once sat at the top of the S&P 500 find themselves falling further and further down the list.  The losses in S&P market cap this year are already in the trillions of dollars.  A decade ago, Citigroup was on the top of the list.  Now with a market cap of $52.5 billion, it ranks 31st, according to data from Thomson Reuters. 

General Electric , parent of CNBC, has also fallen, albeit not nearly as much as Citigroup.  GE now ranks 5th on the list with Johnson & Johnson less than $2 billion away from taking its place in the top 5.  For today, it looks like GE will hold its ground - GE is trading up while JNJ is trading down in the premarket (get extended hours quotes on cnbc.com here).