Confirmed: lazy-loading below-fold slots raised viewability to 79%

Confirmed: lazy-loading below-fold slots raised viewability to 79%
A long-form content site loaded all ad slots on page-load, tanking viewability.
— Below-fold slots loaded 200px before entering viewport
— Top-of-page slot kept eager-loaded for fast first impression
— Wasted impressions (never scrolled to) dropped 38%
Overall viewability went from 58% to 79%, and viewable-CPM buyers re-rated the domain upward over the next billing cycle.
Impact: Serving an ad nobody scrolls to is negative yield. Lazy-load the fold.
Confidence: sourced