@Override
    public StatValue createTrimmed(long startTime, long endTime) {
      if (startTime == this.startTime && endTime == this.endTime) {
        return this;
      } else {
        return new ComboValue(this, startTime, endTime);
      }
    }
Creates a ComboValue by adding all the specified values together.
geode-core/src/main/java/org/apache/geode/internal/statistics/StatArchiveReader.java