Micrometer Histogram does not match timer.count

PrintHistograms.java

package se.flapsdown.micrometer.histograms.bug;

import io.micrometer.core.instrument.Clock;
import io.micrometer.core.instrument.Meter;
import io.micrometer.core.instrument.Timer;
import io.micrometer.core.instrument.distribution.CountAtBucket;
import io.micrometer.core.instrument.distribution.HistogramSnapshot;
import io.micrometer.core.instrument.step.StepMeterRegistry;
import io.micrometer.core.instrument.step.StepRegistryConfig;

import java.time.Duration;
import java.util.Random;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;

/**
* This simple example shows how the histogram buckets does not match the timer.count value.
* It is expected that everything should fit within the buckets and that the value in the last
  bucket should match the total count.
  
  test_with_tag, , max:198.0, bucket: 100.0 = 82.0, bucket: 200.0 = 159.0, Count:163/163
  test_with_tag, , max:198.0, bucket: 100.0 = 84.0, bucket: 200.0 = 159.0, Count:163/163
  test_with_tag, , max:198.0, bucket: 100.0 = 74.0, bucket: 200.0 = 158.0, Count:162/162
  test__no__tag, , max:198.0, bucket: 100.0 = 251.0, bucket: 200.0 = 485.0, Count:488/488

*/
public class PrintHistograms {

    static StepRegistryConfig sc = new StepRegistryConfig() {

        @Override
        public Duration step() {
            return Duration.ofSeconds(3);
        }

        @Override
        public String prefix() {
            return null;
        }

        @Override
        public String get(String s) {
            return null;
        }
    };


    static StepMeterRegistry simpleRegistry = new StepMeterRegistry(sc, Clock.SYSTEM) {

        @Override
        protected TimeUnit getBaseTimeUnit() {
            return TimeUnit.MILLISECONDS;
        }

        @Override
        protected void publish() {

            // Print info about each Timer and histogram
            for (Meter m : getMeters()) {
                if (m instanceof Timer) {
                    Timer t = (Timer)m;
                    HistogramSnapshot histogramSnapshot = t.takeSnapshot();
                    StringBuilder sb = new StringBuilder()
                            .append(getConventionName(t.getId())).append(", ")
                            .append(", max:").append(t.max(getBaseTimeUnit())) .append(", ");
                    for (CountAtBucket cab : histogramSnapshot.histogramCounts()) {
                        sb.append("bucket: ").append(cab.bucket(getBaseTimeUnit())).append(" = ").append(cab.count()).append(", ");
                    }
                    sb.append("Count:").append(t.count());
                    System.out.println(sb.toString());
                }
            }
        }
    };

    public static void main(String args[]) throws InterruptedException {

        simpleRegistry.start(Executors.defaultThreadFactory());

        Random durationRandom = new Random();

        int countTag = 0;

        while (true != false) {

            Timer.builder("test__no__tag")
                    .sla(Duration.ofMillis(100), Duration.ofMillis(200))
                    .register(simpleRegistry)
                    .record(Duration.ofMillis(durationRandom.nextInt(199)));

            Timer.builder("test_with_tag")
                    .tag("count", countTag + "")
                    .sla(Duration.ofMillis(100), Duration.ofMillis(200))
                    .register(simpleRegistry)
                    .record(Duration.ofMillis(durationRandom.nextInt(199)));

            TimeUnit.MILLISECONDS.sleep(5);

            countTag++;
            if (countTag > 2) {
                countTag = 0;
            }
        }
    }
}