@Override
    public AverageAggregationResult clone() {
        AverageAggregationResult obj = (AverageAggregationResult)super.clone();
        if (sum != null) {
            obj.sum = (NumericResultNode)sum.clone();
        }
        return obj;
    }
Returns the average value of the results. Because the result can be any numeric type, this method returns a
{@link NumericResultNode} object.

@return The average result value.
searchlib/src/main/java/com/yahoo/searchlib/aggregation/AverageAggregationResult.java