Tax doesn't take into account voucher code amount
I have successfully applied a voucher code to my eCart, and the correct discount comes up in the cart. However the tax which is set to 20% is still applied to the Sub-total without taking into consideration the discount.
One item added to the cart costing £135
Sub-total = £135
Discount code (set to 5%) = -£6.75
Tax = £27 (still 20% of Sub-total)
Can I get the taxable amount to be (Sub-total minus the discount) please ?
thanks very much for your help