try like :
index=*
| fields eventDateTime,computerName,name,agentGuid,ID
| eval _timeepoch = strptime(eventDateTime,"%Y-%m-%d %H:%M")
| eval myDay = strftime(_timeepoch,"%A")
| eval myYear = strftime(_timeepoch,"%Y")
| eval myMonth = strftime(_timeepoch,"%m")
| where (myDay != "Saturday" AND myDay != "Sunday")
| lookup Workdays myYear myMonth OUTPUT Days
| chart count over computerName by name | eventstats sum(count) as Total by Days
| eval Percent=round(count*100/Total,4)
| eval count=if(Servicetime>100,100.0000,Servicetime)
or
your base search | stats count by computerName name | eventstats sum(count) as Total by Days | eval Percent=round(count*100/Total,4) | ....
... View more