On the Means Test, if you need to take the deduction for tax withholding, use the actual amount taken from your check during the previous six months. The amount of your refund is immaterial for this purpose, although there are other considerations if you usually get a large refund check. Hope this perspective helps!
You should use the average monthly amount during the 6 months. Part of your potential refund could be seen as an asset that you may need to exempt from the trustee.
My answer is general information not intended to create an attorney-client relationship. Seek advice from a qualified attorney to see how the law fits your specific facts. If you are in Washington, please feel free to contact us at (425) 283-0432 to see if we might be of assistance.