At a glance the headline numbers for Shift direction
Which way the shifting content moved.
53.6% of layout shifts push content downwards.
The shift direction mix who uses what, and how fast each group loads
Shift direction. On the fleet: 53.6% down, 46.4% lateral. 36.4% of sites use at least one down.
Lowest-share bucket: LCP 1.6s. Highest-share bucket: LCP 1.6s.
Passing LCP per bucket every category and count level at once - color is the pass rate
Each row is a category, each column its own count bucket (few on the left, many on the right); the cell is the share of those sites passing LCP.
Lateral swings the hardest: 85% of sites pass LCP with few, 76% with many. computed
Few vs many - does quantity cost LCP? the pass rate with few vs many of each category
Per category: the pass rate among pages with FEW of it (hollow ring) against pages with MANY (solid dot), worst trend first. Thin buckets are excluded from the endpoints.
More Lateral costs the most: the LCP pass rate falls from 85% with few to 76% with many. computed
Why this matters for the Core Web Vitals, and where to start fixing it
The direction of a shift is a fingerprint of its cause. Content that moves down means something above it arrived late: an unsized image, an injected banner, an ad slot that grew. Content that moves up means something collapsed or disappeared, like a dismissed notice that did not leave a placeholder. Sideways movement is rarer. It usually comes from a scrollbar appearing, centering changes, or a font swapping to a wider face.
Most pages shift downwards because most late content lands near the top. If your shifts point another way, trust the fingerprint: it narrows the suspect list before you open a single trace.
How does this affect the Core Web Vitals?
Of the 2 categories, Down separates passing sites from failing sites the most. Where Down is rare: 90% pass the CLS. Where it is common: 84%.
Chrome field data from 94,910 sites, representing millions of real page loads. How we measured.