The value reducers that can be applied to a
PickTimeSeriesFilter.
Values:
METHOD_UNSPECIFIED (0):
Not allowed. You must specify a different Method if you
specify a PickTimeSeriesFilter.
METHOD_MEAN (1):
Select the mean of all values.
METHOD_MAX (2):
Select the maximum value.
METHOD_MIN (3):
Select the minimum value.
METHOD_SUM (4):
Compute the sum of all values.
METHOD_LATEST (5):
Select the most recent value.
