Certainly some people have done it. In this memo, I try to demonstrate the odds against beating the market and why one might be satisfied to match the market performance. Should we rely on the good track record of some managers who have beaten the market as proof of their skill. The US stock market is now comprised of over 5,000 stocks. The market for all of these stocks is the stock market.
Stocks tend to move together.
Consequently, we can get a picture of how the stock market is doing by looking at an index. An index is a basket of stocks constructed to represent the whole market or a subset of it. The evening news and the daily papers usually quote the Dow Jones Industrial Average which measures the performance of a basket of 30 stocks. There are many indices. For example there are indices to measure the performance of stocks with large market values and indices to measure the performance of stocks with small market values.