@taxes4739
You have no really good option. Any one you choose could raise questions. I agree with fanfare. If they all have different sales dates and you aggregate them, there is another issue. You could choose one date, but all the others will be wrong. Omitting is the easiest option.
@mberwine
You can choose a purchase date, as long as if it is short term, you choose a date that will reflect that. Short term is one year or less.
