Brian - Though AS 4.4 different data types and different unit of measure for pricing and the use case looks like an Index pricing event (either premium or discounting), it would be hard to execute this type of event in AS 4.4. Either OnD Sourcing 10s1 or 9r1 would be better for this use case since we support Index pricing but not in AS 4.4
If you still want to do this in AS 4.4, you have to create a custom template, turn off price (in Rules), create custom terms (you can name it whatever you want) and assing the appropriate data type (percentage is not supported, so use decimal number instead). You also have to make sure that to incorporate the appropriate language around what you are trying to collect (eg: discount to catalog price or markup etc.)
What category are you trying to run with this particular format?