public Map<String, Double> loadByThread() {
        Map<String, Double> result = new TreeMap<>();
        loadByThread.forEach((name, load) -> result.put(name, roundTo3DecimalPlaces(load)));
        return Collections.unmodifiableMap(result);
    }
Returns the average load of the implied time period, for each thread with non-zero load, with 3 decimal places precision.
zkfacade/src/main/java/com/yahoo/vespa/curator/stats/LatencyMetrics.java