Why do some observations have fewer than seven values in the visits_by_day variable in Advan's weekly foot traffic data?

I noticed some observations in the visits_by_day variable in the Advan Weekly Foot Traffic data have fewer than seven values. In my subset of the data I have about 6 million observations with about 990,000 not having seven values. I downloaded this data a few weeks ago, so I believe it is the most recent version.

Here is an example: the observation with placekey: 22y-222@627-s7v-y9z, date_range_start: 2018-10-29 05:00:00, and date_range_end: 2018-11-05 05:00:00 has the following visits_by_day value: [71,58,63,68,95,49].

Maybe it relates to this post from a few months ago? Any additional information would be helpful as I’m trying to look at this subset of the data at a daily level. Thank you!

I should clarify that out of the about 990,000 observations with fewer than seven values, about 20,700 have values and aren’t just blank observations. These are the observations I’m more curious about.

It does look like the same issue to the post you shared. It seems like daylight savings that week causes there to be a missing day (Sunday) in the data.

Are you only seeing it in 2018? My guess is that occurs each year by the way they calculate the data. They fixed this data in a previous backfill but we added the 2018 after that backfill. I don’t think we’ll be able to backfill the 2018 data.

Yes, it only pops up for date range of Oct 29, 2018 to Nov 5, 2018 which is when the daylight savings change happened. Thanks for the info!