Go to Store > Store Reports > Item Tax to display a report of total sales tax on items.
Each transaction’s item price multiplied by quantity sold less total discounts (using the item price as of the date of each transaction).
Total of all transactions’ tax. This uses the actual tax from each transaction; it is NOT taking the default tax rate multiplied by total item price. It’s possible these may not calculate to be the same if the tax was edited in a transaction.
Net Sales plus Sales Tax