Thanks MatPed. I'm in the same boat - lacking the framework/understanding/statistics skills to answer this...

According to the manual, the real statistical issue under the Balance proxy covers is time/number of trades. Therefore it seems to me that the $500 that's been trading for 9 years will have a higher risk of larger drawdown than the $500 that's only been trading for 1 year. Therefore, it seems I would need to leave more $$$ in the account to protect the older $500 than the newer $500. From the withdrawal perspective, I can't withdraw as much for the older $500 as the newer.

Now what does this really mean? Some possibilities are:

- $300 is the right withdrawal amount, $150 to each $500, and the underlying statistics just works out fine, somehow.

- $300 is the right withdrawal amount, spread in some way between the 2 $500's based on time or ???

- Less than $300 (how much?) is the right withdrawal amount due to the increased drawdown risk of the older $500.

- Other???

Hopefully jcl can clarify.

Thanks!