For Fixed Income. Either Swap Spread or Spread to Benchmark depending upon the order type. Spread to Benchmark: Basis points relative to a benchmark. To be expressed as "count of basis points" (vs. an absolute value).
E.g. High Grade Corporate Bonds may express price as basis points relative to benchmark (the BenchmarkCurveName <221> field). Note: Basis points can be negative.
Swap Spread: Target spread for a swap.