Peak volume

Shrinkage is the share of paid agent time unavailable for handling contacts, covering breaks, training, meetings, absence, and system downtime. Workforce plans that ignore shrinkage systematically understaff, because scheduled headcount and available headcount differ by a predictable and often substantial margin.

Occupancy rate is the portion of an agent’s logged-in time spent actively handling contacts rather than waiting for them. Sustained high occupancy predicts burnout and attrition, so workforce planners treat it as a health measure rather than a productivity target to be maximised.

Backlog is the set of unresolved tickets carried past their target response window. A growing backlog signals that arrival rate has outpaced capacity, and because ageing tickets attract follow-up contacts, backlog tends to generate additional volume rather than simply waiting quietly to be cleared later.

Automation rate is the percentage of incoming contacts handled entirely without a human agent. It measures reach rather than quality, so support teams read it alongside containment rate and satisfaction scores to confirm that automated volume is genuinely resolved rather than simply absorbed and later reopened by the customer.