(17)When only scarce default data is available, the time horizon considered in a rating category should be taken into account for the purpose of the mapping to ensure consistency across ECAIs. Thus, where a short term horizon has been chosen, some items may qualify for a particular level of risk. However, these same items may represent a significantly different level of risk if evaluated over the 3-year time horizon chosen for the calculation of the default rate. This factor should be recognised and appropriately reflected in the mapping.