CountByType countMarkerTypes(Collection<Marker> markersToCount) {
		CountByType countByMarkerType = new CountByType();
		for (Marker marker : markersToCount) {
			String type = markerTypes.getType(marker);
			String subtype = markerTypes.getSubType(marker);
			countByMarkerType.inc(type);
			if (subtype != null) countByMarkerType.inc(subtype);
		}
		return countByMarkerType;
	}