1. Open Rates: High open rates often indicate that subscribers trust and recognize your emails. 2. Click-Through Rates (CTR): A higher CTR suggests that recipients find your content valuable and are willing to engage with it. 3. Unsubscribe Rates: A low unsubscribe rate typically indicates that you are meeting subscriber expectations. 4. Spam Reports: Few or no spam reports signify that your emails are trusted and recognized by your audience.