500 by between 80 and 310 basis points per yeardespite the rapid shrink-
age of the oil sector relative to the rest of the market.
The top-performing stock of the original 20 largest was Socony
Mobil Oil, which dropped the Socony, which stood for Standard Oil of
New York, in 1966 and merged with Exxon in 1999. The second-best-per-
forming stock was Royal Dutch Petroleum, a firm founded in the
Netherlands, and one of the companies that Standard & Poor’s deleted
from its index in 2002 when it purged all foreign-based firms. The third-
best performer was Standard Oil of New Jersey, which changed its name
to Exxon in 1972 and is currently the largest-market-value stock not only
in the United States but in the entire world.
Fourth-best performing stock was Shell Oil, a U.S.-based company
that was purchased by Royal Dutch in 1985. Next was Standard Oil of
Indiana, which merged into BP Amoco in 1998. Sixth-ranking Gulf Oil,
seventh-ranking Standard Oil of California, and tenth-ranking Texas
Co. (Texaco) eventually merged to form ChevronTexaco, while ninth-CHAPTER 4 The S&P 500 Index 55
FIGURE 4–2
Change in Sector Weights and Returns, 1957 through December 2006