{HEAD ~ Data values} are acquired for a set of metrics for {TAIL ~ the target} and each field web site 
{ HEAD ~ Data values } are acquired for a set of metrics for { TAIL ~ the target } and each field web site
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH