code: private DateTime providedOrDefaultFromValue(DateTime from, DateTime to,
  			AggregateCounterResolution resolution) {
  		if (from != null) {
  			return from;
  		}
  		switch (resolution) {
  		case minute:
  			return to.minusMinutes(59);
  		case hour:
  			return to.minusHours(23);
  		case day:
  			return to.minusDays(6);
  		case month:
  			return to.minusMonths(11);
  		case year:
  			return to.minusYears(4);
  		default:
  			throw new IllegalStateException(
  					"Shouldn't happen. Unhandled resolution: " + resolution);
  		}
  	}
docs: Return a default value for the interval start if none has been provided.