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This is the views section of the site analytics visible to 25k users on one of my sites:
That's, uh, not correct. Our site has had its usual activity level during this time. I checked a couple other sites, and the pattern is consistent. This looks like a problem in the analytics data that's coming in; did Google change their API?
Update: Same site a week later; note that in addition to the brief spike of accuracy, page views have dropped to (near-)zero for the whole period, unlike the earlier report. (I know this question has been closed as a dupe, but I thought having the two screen shots together might help somebody.)