A deal between McGraw-Hill and CME Group to bring together the Dow Jones Industrial Average and the S&P 500 index would be a good moment to consider the irrelevance of the former and the significance of the latter.
What does the Dow have going for it? It’s arguably the highest profile stock market benchmark in the world – granted a daily airing by media worldwide. Its composition is stable (the last change was more than two years ago, when Travelers replaced Citigroup, and Cisco replaced General Motors). Its 30 component stocks are highly liquid, which makes the average quick to calculate. It is old. Very old: it was conjured up by Charles Dow in 1896, with a basket of railroads, steel companies and textile mills.
