There a a few regulations that specifically require training with a minimum frequency standard. For example, BSA/AML is one of those topics that requires training for all employees annually at a minimum. You can search the forums for "required training" to find numerous threads where this has been discussed. Other regulation training frequency may not be required by the regulation, but should be dictated by your risk assessment. If you can support your training audience and frequency for most regulation training, that will be sufficient for the examiners.