DIA tracks the Dow Jones Industrial Average, one of the oldest US stock indexes, which holds 30 large US companies chosen by a committee. The index is price-weighted, so stocks with higher share prices have more weight regardless of company size. This is an unusual method and means that stock splits and share price changes affect weights. The 30 holdings include companies such as Apple, Goldman Sachs, Microsoft and Visa. With only 30 stocks, the index is narrower and less diversified than the S&P 500, but over long periods the two indexes have moved in a similar way. DIA is structured as a unit investment trust and pays dividends monthly.
