code: private boolean doesAnyTimeSeriesHaveData() {
  		for (int i = 0; i < iterators.length; i++) {
  			if ((timestamps[iterators.length + i]) !=  MARK_END_TIME_SERIES) {
  				return true;
  			}
  		}
  		return false;
  	}
docs: Indicates if there are values still to be read from any time series, by inspecting the internal timestamp buffer