Apple Sleep App 6 Month Tracking Inaccurate

Solution: the standard view of the data is the “stages” view. Using the Amounts view solves the issue.6 months —> Show more sleep Data —> Amounts

Cause: I don’t know why AVG TIME ASLEEP is shown wrong when looking at stages. It seems they calculate the average “sleep start” and “sleep end”. But that also doesn’t make sense, and also I can’t find the way they would calculate this. Maybe they use a kind of elastic day, where a day ends when you go to sleep, not at midnight.Here is what I have tried:

Night 1 2020-04-16 10:00 PM 2020-04-17 4:00 AM

Night 2 2020-04-18 1:00 AM 2020-04-18 4:00 AM

On a weekly and monthly basis, my health app calculates an average of 4h30min sleep time, but on a 6-month basis, it calculates an average of 6 hours. Also, 6 months (when not looking at amounts) shows: Sleep starts 11:30 PM and sleep end 5:30 AMAssuming these averages are simple arithmetic means, the average start time is (10:00 PM + 1:00 AM)/2, and the average end time is (4:00 AM + 4:00 AM)/2. However, the issue with this is that time doesn't function like regular numbers due to the cyclical nature of the 24-hour clock. If you consider 1:00 AM as 25:00 (in a 24-hour format, considering it as an extension of the previous day), then the average start time would be:(22:00 + 25:00)/2 = 23:30 (or 11:30 PM)That aligns with Sleep Start in the Health app. But not with sleep end.

I have the exact same issue. Sleep average is around 6,5 hours per night, weekly and monthly averages show this… but 6 month average show around 7,5 hours… and it simply is not true. How can this be fixed?

Hahahah.

Good idea. I have submitted the request here Feedback - iPhone - Apple

Also it seems to affect not only some users. I have checked the data of some friends and these were also calculated incorrectly.

Here is what I have submitted:

Subject: Wrong calculation of sleep data in 6-month view

Feedback Type: Bug Report

Comment: AVG TIME IN BED and AVG TIME ASLEEP are calculated wrong in the 6M-View. 

In the 6-month view, an AVG time is calculated that is higher than the average time of all previous months. Such an average value is mathematically impossible. 

If you compare the view of the steps with the view of the amounts under "Show more sleep data", the incorrect calculation becomes visible (affects only 6M-View).

I am having the same problem.

Been tracking sleep for almost a year. My daily, weekly, and monthly average shows about 6 hrs 10 minutes.

The six month average shows almost 8hrs.

I have the ‘in bed’ part turned off, so it’s only taking info from my apple watch.

The daily/weekly/monthly is correct. Why have they not corrected this obvious error?

Ha ha, I’m from England. The umlaut is a respect to your language for improving the alphabet flexibility, hence username options!

There’s a clear error here that Apple need to investigate and resolve rather than it taking up our time. How about we report it to Apple formally and anyone else coming across this thread also can also do so until they resolve the issue? The problem seems to extend beyond just iPhone, but maybe we can just start with submitting to the form here:

Feedback - iPhone - Apple

That's an awesome tip, thanks. Any idea on how Apple screws up 6M sleep amounts when viewed under stages. It literally shows my 6M average as 11h, 27m vs. the actual 7h,48m shown under amounts (which lines up with my 7h,26m monthly, and 7h,28m weekly). That's a 4h per night average error.

It's truly amazing that Apple can't figure this out after years when it touts the health management features of its products. (Good thing they don't have to worry about cars anymore).

I have submitted it here: Feedback - iPhone - Apple

Here is what I have submitted:

Subject: Wrong calculation of sleep data in 6-month view

Feedback Type: Bug Report

Comment: AVG TIME IN BED and AVG TIME ASLEEP are calculated wrong in the 6M-View. 

In the 6-month view, an AVG time is calculated that is higher than the average time of all previous months. Such an average value is mathematically impossible. 

If you compare the view of the steps with the view of the amounts under "Show more sleep data", the incorrect calculation becomes visible (affects only 6M-View).

The strange thing is that it seems to affect everyone. I have checked with several people and the same error occurs on all of these users. However, when I phoned support, the employee asked his colleague if she had noticed the problem. Since she said no, he thought it was an individual case. I replied that just because she hadn't noticed it didn't mean it wasn't there. I seemed to have convinced him a little, and he assured me that he would look into the problem. Unfortunately, nothing happened.

It seems Apple calculates the difference between the average sleep start time and the average sleep end time over 6 months.

Noone has ever told them how to calculate average time duration properly.

Why has Apple not fixed this? Basic.

The more I dig into this, the more errors I find in Apple’s numbers and summarised data (average in bed start time is typically about 5mins out, and the end time is way way late compared to the daily data recorded). Some data errors also seem to also extend to other time periods (not just 6M). The source of historic phone captured data also seems to show your current phone if you transfer to a new phone (eg it’s showing that my 2022 ‘in bed’ data was captured by my current iPhone 15 Pro). Think Apple need to do a full audit of this sleep data and the summarisation statistics.

Okay, I just realized that not only the 6-month view is wrong, but all the others as well. Unfortunately, the amount view doesn't help. In my example, only the 6M amounts view was correct but not for other time periods.

I have tested the following:

Added sleep from 1:22 PM until 6:22 pm (5 hours)

4:38 are put on the first day and 22 min is put on the next day. I don’t know why. Timezone or whatever.

Month view: sometimes says 4h38 and 2h30

2:30 because 4:38 on 1 day and 00:22 on the next day, averaged 2h30.

I’m also having issues with the 6M option. The solution someone else suggested with going to “amounts” instead of “stages” isn’t helpful to me because I’m looking at sleep stages. My real percentages should be: REM 22% CORE 62% DEEP 14%, that’s consistent when checking the past 6 months with the 1M option.

When switching to 6M my percentages change into this: REM 16%, CORE 72% DEEP 12%. It’s not a HUGE difference but when I’m analyzing my sleep data it needs to be accurate, if I saw that my REM was 16% not noticing that it’s inaccurate, I would start to worry.

I don’t understand why this hasn’t been fixed yet, it can’t be intentional.

right.

The "stages" view for 6month is definitely way off.

Im not sure about the amounts view.

It says the following:

Average REM: 55 min

Average Core: 5 hr 57 min

Average Deep 29 min

total would be: 7 hr 21 min

however in 6M stages view it says: AVG TIME ASLEEP 8 hr 22 min

in 6M Amounts view it says 6hr 20 min

So there is definitely something wrong with the sleep data. Also if adding sleep data manually it also behaves very weird.

Did you mean AM rather than PM? I wondered whether you have your sleep hours set to end at 6? Sometimes I notice that the metrics stop at my wake up time rather than when I actually woke up (so maybe it puts the remainder into the following day?) I have the same issue as you - struggling to figure it out. Is there a place we can report the bug to Apple?