If you have heard fund managers talk about the way they invest, you know a great many employ a top down approach. First, they decide how much of their portfolio to allocate to stocks and how much to allocate to bonds. At this point, they may also decide upon the relative mix of foreign and domestic securities. Next, they decide upon the industries to invest in. It is not until all these decisions have been made that they actually get down to analyzing any particular securities. If you think logically about this approach for a moment, you will recognize how truly foolish it is.

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