How does fitbit handle HR data on 24h scale (older devices)

[Liliacea]

How does the older Charge 2 deal with HR data on a 24hr scale and what happens with this data on the dashboard/app? Does Fitbit use an average over a certain time interval and throw some smoothing/moving average over it? I'm asking because my heartrate sometimes drops to very low levels and this isn't reflected in the data. Likewise a sudden start and associated elevated heartrate for a short time is not visible either, while the fitbit does show these high/low readings at that moment. Is there a difference between day and night measurements?

[LZeeW]

@Liliacea   I apologize if I misunderstand your question.  When you tap on your heart rate tile and look at a 24 hour graph, you can press lightly and a number will show with a heart rate value and a time.  That value is a heart rate average over five minutes.  When you look at a heart rate trace from exercise details, that value is over one minute.  If you are a premium user and you get your sleeping heart rate, that graph is also in one minute intervals.

This is why your graph from the heart rate tile looks different from and smoother than either exercise details or the sleeping heart rate graphs.