abstract fun observeAnxietyData(daysBack: Int): Flowable<List<AnxietyData>>
Returns Flowable that emits list of anxiety in sleep for day
daysBack ago sorted ascending by time.
Data before specified day could be returned if they fall into sleep started before midnight. See Sleep for more information.
anxiety in sleep always fall into sleep episodes (e.g. there will not be any anxiety in sleep outside of a sleep episode and there will be no anxiety in sleep at all if there are no sleep episodes).
Flowable that emits list of anxiety at sleep data for night
for how many days ago in relation to today information is needed.