The level on which the cap is to be applied.
||The cap is applied at the creative level.|
||The cap is applied at the ad group level.|
||The cap is applied at the campaign level.|
||This value cannot be set by the user and sent to the AdWords API servers, as it would generate a RejectedError. It can only be received by the user from the AdWords API servers and it means that a new value available in a newer API release version is not known in the current API release version. If the user encounters this value, it means an upgrade is required in order to take advantage of the latest AdWords API functionality.|