Notes

I think it needs to be qualified by these questions:

* What instrument are you trading?
* What is the tick value?
* What is most you are going to risk on any one trade? (has to be 3% or less)
* Do you have a strategy that fits the 3% or less rule?
* What is your account minimum? This should be calculated on the smallest account size needed not to exceed 3% of capital on any one loss. Using 6e as an example; if your stop is set up to lose a maximum of 200 dollars then the minimum account size needs to be 7000. (7000 * 3% = 210)
* How many consecutive losses would it take before you have a margin call or reach the account minimum? This is a important question. A trader should be able to lose >30+ trades in row before your account blows up. For example, my strategy allows me to lose 80 consecutive trades in row

.

Applying those question to 6E:

* What instrument are you trading? 6E
* What is the tick value? 12.50
* What is most you are going to risk on any one trade? (has to 3% or less or account capital) $200.00
* Do you have a strategy that fits the 3% or less rule? Yes
* What is the required margin (for futures) 5,400 on MB trading. Used overnight margin.
* What is your account minimum? 7000. Using the 3% rule as explained above. (7000 * 3% = 210)
* What is the minimum consecutive losses your account can endure before hitting a margin call or account minimum is hit ?(should be >=30) 50

Formula:

Minimum account value = (maximum loss per trade * minimum consecutive losses (>=30)) + Margin or Account Minimum (whichever is larger)

(200 * 50) + 7000

Minimum account value: 17,000

edit: I did not include commission or slippage in the calculation. This should be added to your maximum loss per trade.