The number of documents that contain a value in the specified field in the result set.
The maximum value found in the specified field in the result set.
The average of the values found in the specified field in the result set.
The minimum value found in the specified field in the result set.
The number of documents that do not contain a value in the specified field in the result set.
The standard deviation of the values in the specified field in the result set.
The sum of the field values across the documents in the result set. null for date fields.
null
The sum of all field values in the result set squared.