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Methodology Details
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A description of the methodology:

I assumed a complete rebalance to the target allocation at the beginning of each year (after withdrawal of that year's living expenses). I ignored any associated tax consequences associated with this action. 

I analyzed retirement starting years from 1926 through 1979 inclusive. This is a total of 54 different 30-year retirement scenarios.

For starting years after 1969 that would have included years later than 1998 (the last year for which I had data) I simply ‘rolled over’ back to 1960, 1961, etc. The choice of 1960 was a strictly arbitrary choice.

I did not do a complete MVO (Mean Variance Optimization), but the playing around that I did indicated to me that Long Term Bonds (government or corporate) offered very little value so I ignored these two asset classes in my asset allocation.

I used a 5% short term (treasuries) allocation in all cases because nothing else seems practical to me (even index funds tend to have a couple percent allocation to cash in most cases).

I ignored any investment expenses (fund expenses, broker’s fees, etc.) that might be encountered in practice.

Each withdrawal was made at the beginning of the year and placed into an account (in practical terms probably an interest bearing checking account) whose net return was .33 x initial value x Treasury Bill return. I was trying to simulate the return of that checking account across the year (average balance of approximately 50% of the withdrawal at the beginning of the year and earning somewhat less than Treasury Bills).

The most straight-forward use of this data would be to treat taxes just like any of your other expenses.