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Foreign visits into the U.S. fell off a cliff in March

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Re: Foreign visits into the U.S. fell off a cliff in March

#6
> And I rolled it over 30 days to be able to show any recent changes while not getting lost in the noise of daily change.

small thing, but learned at work that often there's a weekly pattern (and I'd bet there is for airplane travel) so you ought use a rolling 7 day average instead of 30 because there are different numbers of weekends in each day's 30 day number.

This is why there's a slight zigzag in the line charts in the article.

Re: Foreign visits into the U.S. fell off a cliff in March

#9

> And I rolled it over 30 days to be able to show any recent changes while not getting lost in the noise of daily change. small thing, but learned at work that often there's a weekly pattern (and I'd bet there is for airplane travel) so you ought use a rolling 7 day average instead of 30 because there are different numbers of weekends in each day's 30 day number. This is why there's a slight zigzag in the line charts…

Or use 28 days ? If we need to average both weekly and monthly trends
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