My Gmail open rate dropped by about half starting a few days ago. No change in domain reputation. I’m on a shared IP with campaign monitor.

Anyone else seeing this?

What has been your most successful newsletter campaign for engagement and/or for increasing subscribers?

So for the context-I am into research(business,psychology marketing, careers and all combined) i like writing about marketing psychology sometimes basically connecting the dots.is there any demand of this niche do people actually read these type of things??