PetroChina, largest company in emerging markets, is worth more to stock investors than the biggest U.S. banks combined. The Bloomberg chart below shows the market value of the KBW Bank Index, which tracks 24 of the largest American lenders, plunging to $272.4 billion last week from a peak of $1.36 trillion two years ago. The gauge tumbled 51 percent in 2009 to the lowest level since October 1992. Citigroup and Bank of America lost more than 70% of their value on concern the U.S. government will nationalize the lenders and wipe out stockholders. While PetroChina's shares have dropped 71%from an all-time high in November 2007, they rallied 35% since 27 Oct 2008. That pushed the oil producers market value to $285.1 billion, surpassing the U.S. bank index for the first time. China's Shanghai Composite Index rallied 24% this year for the top performance among stock benchmarks worldwide while the S&P500 Index retreated 15%.