For each metric within the set of metrics, {TAIL ~ a best data value} acquired for the metric from among all field web sites is assigned as a bounding data value for {HEAD ~ the metric} 
For each metric within the set of metrics , { TAIL ~ a best data value } acquired for the metric from among all field web sites is assigned as a bounding data value for { HEAD ~ the metric }
OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD