1. Highest tax rate in cart
2. Lowest Tax Rate in Cart
3. Flat Tax Rate
The tax rate used for “Flat tax rate on taxable cart” is based on the selected “Tax class for shipping” via System > Configuration > Tax > Tax Classes.
4. Highest value in the cart
5. Weight Proportion in Cart
The cart contains 1 x sofa piece (2lb) and 1 x phone (0.5lb) for a total of 2.5lb. The shipping is a flat rate of $10.
- Proportion of cart weight of the sofa piece is 0.8 therefore the proportion of shipping charge is $8 taxed at the sofa piece’s tax rate of 10% = $0.80
- For the phone, the proportion of weight is 0.2 therefore the proportion of shipping charge is $2 at a tax rate of 18% = $0.36
- This gives a shipping tax total of $1.16