bug in aggregation code

CalculateAggregate.java

private AggregateNumericMetric calculateAggregate(Iterable<AggregateNumericMetric> metrics, long timestamp) {
    double min = Double.NaN;
    double max = min;
    int count = 0;
    ArithmeticMeanCalculator mean = new ArithmeticMeanCalculator();

    for (AggregateNumericMetric metric : metrics) {
        if (count == 0) {
            min = metric.getMin();
            max = metric.getMax();
        }
        if (metric.getMin() < min) {
            min = metric.getMin();
        } else if (metric.getMax() > max) {
            max = metric.getMax();
        }
        mean.add(metric.getAvg());
        ++count;
    }

    // We let the caller handle setting the schedule id because in some cases we do
    // not care about it.
    return new AggregateNumericMetric(0, mean.getArithmeticMean(), min, max, timestamp);
}