Can a lumpsum amount be applied at the order header level

Hi,

We would like to apply a lumpsum amount at the order header. When setting up modifiers, I only see Percent for order header level modifiers. The user guide also appears to confirm this.

Does any one know if there is a way to apply a lumpsum amount as a discount at the order header level?

Example:

Line 1 = 10 UNITS at $100 = 1000

Line 2 = 1 UNIT at $555 = $555

ORDER TOTAL : $1555

LUMPSUM DISCOUNT APPLIED AT ORDER LEVEL: $55

NEW ORDER TOTAL TAKING DISCOUNT INTO CONSIDERATION: $1500.

Thanks in advance!