Dow Jones

stock index is the oldest US index. Having emerged as an indicator of the state of the largest industrial sector in the US economy, nowadays it covers the 30 largest American companies from different industries, such as, Coca-Cola and Boeing.
It has been published since May 26, 1896.

The Dow Jones Index reflects the dynamics of the 30 largest US companies and is more vulnerable to influence from each of them than the more complex S&P 500.