Sudden RPM/CPM Drop After Ad Density Test and Site Layout Changes

I’m reaching out because I’ve been seeing a significant drop in RPM and CPM after testing ad density settings and making some layout adjustments. I’d like your help in checking if this is part of the normal adjustment period or if there’s a technical issue on my account.

Here’s the situation step by step:

• Before changes, my site was consistently earning 25–35 RPM with CPM above $1.00.
• A few days ago, I switched Ad Density from Optimal to High. For the first 2 days, RPM dropped to 12–14 and CPM went down to $0.69–0.82.
• I noticed a small upward trend during those 3 days (RPM and CPM increasing slowly).
• After 3 days on High, I decided to roll back to Optimal.
• At the same time, I also implemented some site-level optimizations (font size increase, shorter paragraphs, more headings, extra images, etc.).
• Since rolling back, RPM has fallen further: 15 → 8 over the last two days, even though:
  • Traffic volume has remained steady (around 1000 sessions/day).
  • Traffic sources and geo mix are the same as before (mostly Tier 1).
  • Ads.txt is up to date.
  • Seasonality shouldn’t explain such a sharp drop.

Given this, I’m worried something might be wrong with ad delivery, bidder adjustments, or viewability on my site.

Could you please:

1. Check my account and confirm if everything looks normal from your end.
2. Let me know if the drop is part of a short-term learning/adjustment period.
3. Advise if I should keep my settings stable and wait it out, or if further adjustments are needed.

Thank you for your help in diagnosing this. I’ll be happy to share any additional data (screenshots, impressions per session, breakdown by device/geo) if that helps.