Google had announced on 2nd June 2019 that, they are going to launch June 2019 Core update. This broad core algorithm update was done several times per year. June 2019 Core update was live on 3rd June 2019, and started rolling out in various data centers later days.
Some SEO toolset provider companies, including Sistrix, RankRanger, SearchMetrics and Moz have provided analysis about ranking of websites on basis of Google June 2019 Core update. But remember google index is a huge figure, but the measurement of the ranking by these SEO tool providers are like miniature in the comparison.
Sistrix has provided some website examples with their Domain name, visibilities and percentage of gain. Main gainers of sistrix are from mostly .uk websites.
RankRanger which is a big farm in SEO tool providers has analyzed that, rank fluctuations increase by niche. Mostly fluctuated niches are Travel, Retail, Health, Finance, and Gambling.
SearchMetrics has announced, they are still working on the data and said, Google has reverted some factors, which were changed on March. In medical category like webmd.com or verywellhealth.com lost their visibility and gained back now after update. They have also observed areas like UGC or Q&A are not getting improved.
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