The 202105 dataset is live

[Rick Viscomi]

Hi CrUX users,

This is your monthly announcement that the latest dataset has been published to BigQuery.

The 202105 (May 2021) dataset is now available and it covers 8,411,670 origins. Here's a look at origins' Core Web Vitals performance this month:

• 50.7% of origins had good LCP
• 89.9% of origins had good FID
• 60.4% of origins had good CLS
• 29.2% of origins had good LCP, FID, and CLS

Some important product updates in this release to make you aware of:

• Starting in this release, CLS will be capped at session windows at most 5 seconds long with a 1 second gap. See Evolving CLS in web tooling by Addy Osmani and Elizabeth Sweeny for more info.
• The previous CLS implementation will still be available for a limited time in BigQuery under the name `experimental.uncapped_cumulative_layout_shift`.
• The LCP implementation now reflects the API changes that landed in Chrome 88 in January.
• The FCP good and poor thresholds have been updated in the CrUX Dashboard and `materialized` tables to 1.8s and 3s respectively. This change applies to all historical data as well.

And we have two community resources to highlight this month:

• The almost-complete guide to CLS by Jess Peck, an extremely detailed and informative look at how to measure and fix layout stability issues
• CrUX and Core Web Vitals on the JS Jabber podcast, in which Rick Viscomi from CrUX DevRel (moi) talks about measuring the state of the web

If you have any questions about CrUX, feel free to reach out to us on any of these channels:

• chrome-ux-report on Google Groups
• @ChromeUXReport on Twitter
• questions tagged with chrome-ux-report on StackOverflow
• GoogleChrome/ChromeUXReport on GitHub
  

Cheers,

Rick