Standard & Poor's 400 Stock Index
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Standard & Poor's MidCap 400 Index
Standard & Poor's 400 Stock Index (S&P 400)
A broad-based index of 400 industrial stock prices weighted on the basis of market value (stock price multiplied by shares outstanding). It includes listed and over-the-counter stock but is heavily influenced by the stock of large corporations. The index is based on a value of 10 during the period 1941-43.