For labor efficiency reporting, an efficiency variance compares standard hours allowed for actual output with actual hours, valued at the standard labor rate. Finance must define the output, hours, rates and sign convention used. Camera observations can help investigate visible cycle and method differences within that period. They do not replace payroll, attendance or accounting records. Reconcile the scopes before using station results to explain a monthly variance, and treat unseen causes or concurrent changes as unresolved until the team checks them.