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Morgan Stanley, Merrill Lynch and the Fable of Three Bulls

August 05, 2007
FOUR FACTORS MODEL AT A GLANCE
The concept of maximum earnings market share is straight out of microeconomics 101. You start by expressing your company's earnings after enterprise marketing expenses as a function of its market share in a strategic group. Then you take the first derivative of this function and solve for that market share where the difference between marginal costs and marginal earnings is zero. That's maximum earnings market share, symbolized in this chart as "m hat."

Two of these factors are outside your control: competitors' enterprise marketing expenses (f) and strategic group revenues (R). Happily, the two factors are under your control: your percent gross margins (g dot) and enterprise marketing efficiency (x). When competing for customers, gross margin and marketing efficiency rule.

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