Thank you for this suggestion! Unfortunately we don’t currently have a way to track the specific items that were taxed at the time of purchase, but a simple way to come up with that number is to use the sales tax you collected and work backwards from it. For example, if your tax rate is 10% and you know that $450 in taxes were collected, you can know that the total taxed was $4500. The formula for that is just [total tax collected]/[tax rate]. In this example it would be 450/.10 = 4500.