Why are there only 30 stocks in the Dow? The case for (& against) a narrow index

Some investors pay close attention to the moves of the Dow, while others devote their attention to larger indexes. Below are some of the advantages and disadvantages of monitoring the 30-stock index.Below is a table of the stocks that make up the Dow, sorted by their sector.The index originally consisted of 12 stocks in the industrial sector. In 1916, the index expanded to cover 20 stocks, and then it grew again in 1928 to its present 30-stock format. The measure now aims to cover sectors that represent the ...