HKCumulativeQuantitySample does not accumulate values

Hi,

My app reports daily step counts, and I’m trying to use HKCumulativeQuantitySample to report them to HealthKit by adding such objects with each update:

let sample = HKCumulativeQuantitySample(type: .stepCount, quantity: HKQuantity(unit: HKUnit.count(), doubleValue: dailyTotal), start: startOfDay, end: nowDate)

However, HealthKit interprets them as regular samples—it sums them into a global aggregate instead of updating the daily cumulative value. So if I report the daily step count as 500 and then 550, HealthKit interprets it as 1,050 steps instead of 550.

Is this expected behavior? If so, what is HKCumulativeQuantitySample intended for, and how should it be used? I’m struggling to find any examples.

Thank you

HKCumulativeQuantitySample does not accumulate values
 
 
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