Include the purchase date for Products and Expenses, which is already required and collected, in the CSV and other export options. The current behavior seems to be to groups all Products and Expenses at the end of an invoice without showing the collected purchase date, making it impossible to associate correctly with one or more tickets on the same invoice above. Including the purchase date would clarify the invoice and avoid manual work to type the same date already collected by the system into other fields to provide a reference.