Account minimums and timing

The Global Investment Performance Standards (GIPS®) permit firms to establish a minimum account size. This minimum is intended to represent the threshold, below which accounts aren't able to represent the composite's strategy. While many compliant firms, no doubt, use it as the minimum that they will accept, that's not the intended meaning.

Minimums are an option, however, and not everyone uses them. But if you do, how do you decide when to remove an account (when they fall below the minimum), and when to put it in (when it rises to or above the minimum)?  Some firms use the beginning market value as the determinant for removing an account. But is this appropriate?

Let's say that your minimum is $1 million, and an account's value on June 30 falls to $940,000. This would mean, given this approach, that the account will be included in June but removed in July. While this is permitted, does it make sense? If your minimum truly means that below this level the account isn't representative of the strategy, does it belong in the composite in June? Would it not make more sense to remove it from the composite if the ending value is below? What if it had dropped all the way down to $50,000? And what if it dropped because on June 5 the client made a huge withdrawal? Clearly the account that month doesn't represent the strategy. And yet, based on this rule, it would be there and its return would influence the composite's.

My suggestion: include it based on the beginning of the month value and remove it based on the ending month value. Meaning, that if, for example, at the start of June the account has risen above the threshold, it's included in June; if at the end of August if it falls below, it's out for that month.

Does that make more sense? Thoughts?