The Tax By button is used to toggle the method by which the sales tax rate is based (between percent or dollar amount).
Percent - A percentage of the taxable amount. Enter the percent as a percentage. For example, 3 = 3% or .03 = 0.03%.
Dollars - A dollar amount tax (Per unit sold). Fractional amounts are calculated for fractional quantities sold. For example, 3 = $3.00 or .03 = $0.03.
See:
Tax Tables - General Information
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