Use Flat Rate

Key Use Flat Rate in Credit Curve refers to the boolean that determines whether a flat hazard rate is used as input or not.
Set TRUE to build the curve by providing only a flat hazard rate.
Set FALSE to build the curve by providing a number of credit instruments, in which case the curve is constructed in a piecewise fashion as follows:
Each segment is determined sequentially starting from the earliest period to the latest and is chosen so that the instrument whose maturity marks the end of such segment is correctly repriced on the curve.
The bootstrapping algorithm will raise an exception if any two instruments have the same maturity date.