https://mongodb.github.io/mongo-csharp-driver/2.12/apidocs/html/M_MongoDB_Driver_Linq_MongoEnumerable_StandardDeviationPopulation__1_9.htm
MongoEnumerable.StandardDeviationPopulation(TSource) Method (IEnumerable(TSource), Func(TSource,...
Computes the population standard deviation of a sequence of values that are obtained by invoking a transform function on each element of the input sequence.
methodienumerablefunc
https://reference.opcfoundation.org/Core/Part13/v104/docs/5.4.3.39
UA Part 13: Aggregates - 5.4.3.39 StandardDeviationPopulation
uapartaggregates