Repeated events over a certain amount of time = flag

[charlienhill]

Hey team, this is likely answered elsewhere, so feel free to just point me to it.

I need to produce a report of devices that report a certain data point repeatedly over a certain amount of time.

Example: if a thermostat reports >80deg for 3 of the 4 past reporting periods, that = a sustained high-temperature condition.

Can someone direct me on how to achieve this?
Thanks