By default, only one tier will be used to calculate the item's price on a per unit basis when selecting Tiered Per Unit Pricing as the Pricing Structure. If, however, the **Stepped Pricing** checkbox is checked in the settings (shown in the screenshot below) the item's per unit price will use all tiers to calculate the item's price:

For example, if the first tier is $5.00 and the second tier is $10.00 with a quantity of 20, the unit price will be calculated as follows:

The first 9 calculated at $5.00 per unit equalling $45

The next 11 calculated at $10.00 per unit equalling $110

The **Total Price** of the item will be $155 which will calculate the **Unit Price** by dividing the **Total Price** ($155) by the **Quantity** (20) for a **Unit Price **of $7.75: