There are no mandates for reviewing fair lending - it is a management and risk issue. You should have a self-assessment, reflecting the risks and how important that they are (risk profile), issues and compensating controls.
When examiners review fair lending, one area of concern in the review is on redlining. Usually, they look at the assessment area, penetration into all tracts and identify those tracts which may be underserved. A concern might be if there are LMI and/or majority minority tracts which are underserved and the creditor is completely unaware that they are, or more importantly the why they might be underserved.
Since in most cases, examiners utilize the annual HMDA reporting, many lenders annually analyse the redlining aspect to identify if any tracts are underserved, the reason "why" and come up with a mitigating plan. As part of compliance risk management, IMHO, regulators will give more credence to an institution that had an issue, discovered it on their own and identified corrective action than to a bank with no exceptions, but only because of happen-chance. There were no plans, policies and/or procedures to check. Additionally comparison to peers and competitors is usually geared to annyal HMDA reporting, as it is the easiest to aggregate.
Differences in approval rates, etc, can be done for any period, as underwriting usually goes from one year to the next.
Yes, you can look at your data every 18 months, annually when you file HMDA, or ignore and wait for the regulators to identify issues. IMHO, it would be based on your risk tolerance, past performance, self-assessment and controls built into your systems.
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