% Change in Position - percent of the change for your position in the underlying.
For example, say you have a Net Liquidation Value of 40,000. XYZ shows a current ask price of 80.00. If you create a buy order for XYZ, select "% of NLV" as the Quantity Type and enter "20" in the Quantity Value field, you're telling the application to calculate the number of shares you could buy for 20% of $40,000 or $8000.00, based on the Ask price of $80.00. The calculated Order Quantity value of "100" is then displayed in the Quantity field.
To display the Quantity Type and Quantity Value fields
Right-click on any column name in the Order Management section of the trading screen, and click Customize Layout.
Click the Order Columns tab. In the Available Columns list in the Quantity section select Quantity Type and Quantity Value and Add them to the Shown columns list.
In the Quantity Type field, select the currency type. This field assumes the base currency.
In the Quantity Value field, enter a currency amount. For a buy order, enter the amount you want to spend. For a sell order, enter the amount you want to make. Based on the current bid/ask, your value gets rounded up or down.
The order quantity is calculated and displayed in the Quantity field.
To calculate order quantity by Deliverable Value (DLV Amount)