How to not let next year's advance invoice payment appear on this year's reports

[Zhang_Weiwu]

Hello. Some customers paid me for my services to come in year 2012, I
posted the invoice, got the payment. One stake-holder is pulling out of
the business by the end of the financial year and demand his 50% share
of asset, which is easy to calculate by checking equity statement. But
he would then take the 50% of the advance payment, a payment that
doesn't cost him.

It would be great if there is an option to leave out selected invoices
when closing the book.

I hope there is a way to exclude advance payment so that they do not
appear as asset in reports. Since the payment is made, causing the
invoice date read-only, is postdating the invoice using UPDATE SQL TABLE
the only way? (If true, I'd rather prefer not doing it, and calculating
his share separately after-the-report.)

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