Optimal Bond Portfolio

[captn]

On pages 9 to 12 of feldblum's Taxes and Investment Strategy paper he discusses on how to determine the optimal investment strategy with respect how how many tax exempt and non-tax exempt securities to buy.

Feldblum says that the fraction of AMTI/RTI of 1.75 is optimal...but i don't see where it says why that is the optimal ratio.

Can somone explain to me how this optimal fraction is computed?

thanks in advance.

[carrytheCrøss]

http://www.actuarialoutpost.com/actuarial_discussion_forum/showpost.php?p=2802284&postcount=4

[triplea]

So be careful if they ask a question on that and change the tax rates.