When the marginal return on assets begins to approximate the marginal costs of borrowing, says Ken Fisher.

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When the marginal return on investment from acquisitions risks being low, distributions to shareholders should be more substantial, Peris says.

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So in order for the marginal return to be attractive, you have to consider the presence and financial terms around those sunk investment costs.

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One important element of that legislation was that the personal marginal income tax rate structure would return to its 2000 level on January 1, 2011.

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However, with respect to return on assets, Acadia Healthcare looks attractive at 3.9%, a marginal premium to the peer group average of 3.5%.

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