This OPC UA Property, of DataType UInt32, is the PreviousCount parameter for the object’s event algorithm.
The PreviousCount value represents the value of pMonitoredValue at the time the most recent transition to NORMAL was indicated. Upon initialization of the event algorithm, this parameter shall be set to the value of pMonitoredValue. When a transition to NORMAL is indicated, this parameter shall be updated to the value of pMonitoredValue.