There is little difference between static spread method and static cash flow rate of return method in the case of concentrated cash flow, but there will be great difference in the case of scattered cash flow. Generally, the maximum cash flow of corporate bonds is concentrated on the maturity date, so the pricing methods of static spread method and static cash flow yield method have little difference for the price of corporate bonds, but not necessarily for securitization products. Many bonds produced by securitization are debt-paying bonds, which are characterized by the fact that the inflow of cash flows is evenly distributed in various periods rather than concentrated in a certain period, so it will be more accurate to evaluate them by static spread method.
Generally speaking, the flat yield to maturity curve is rare, and the spot yield to maturity increases with the extension of the term, reflecting the long-term uncertain risk premium. Therefore, the static cash flow rate of return method is only applicable to the pricing of securitization products with short-term and concentrated cash flow; The static spread rule is applicable to the pricing of securitization products with long-term and unified cash inflows. But in any case, a mature national debt market that can provide spot yield curves with different maturities is the premise of its correct pricing.