Multiplier applied to the benchmark rate, expressed as a decimal fraction of 100%. 1.00 = 100% of the benchmark. 1.10 = 110% of the benchmark. 0.95 = 95% of the benchmark. This is not added to the benchmark—use margin for an additive spread.

If you do not pass a value for benchmark, this field must be null. Otherwise, it's required.

Additive spread, in the same unit and period as the benchmark rate: nominal annual, decimal fraction. If benchmark is 0.025 and margin is 0.0225, the resulting annual rate is 0.0475.

If you pass a value for benchmark, this field is optional. If benchmark is null, this field must be null also.