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Google's John Mueller posted one of those short question and answer videos the other day, this one was on why do the Google Search Console graphs sometimes fluctuation. The answer is maybe something Google changed on their end or something you changed on your end - no kidding.
John said two reason why the graphs may show changes:
(1) Google search ranking and indexing changes can cause it.
(2) A new piece of content might be doing well and cause fluctuations.
Google said you should:
(1) Not worry about small fluctuations.
(2) If you see trends up or down over time, that may be something to keep an eye on.
(3) If you see big spikes in changes, then that massive spike might be a more serious change that you should investigate.
Here is the video - it really doesn't give you much to work with but hey...
Forum discussion at Twitter.
